pmid
int64
5.38k
34.5M
doi
stringlengths
8
72
year
int64
1.92k
2.02k
journal_title
stringlengths
2
239
journal_iso_abbreviation
stringlengths
2
79
title
stringlengths
1
569
abstract
stringlengths
1
16.5k
category
stringclasses
2 values
subcategory
stringlengths
3
35
30,093,351
10.1016/j.schres.2018.07.042
2,020
Schizophrenia research
Schizophr Res
Social reward processing: A biomarker for predicting psychosis risk?
The desire to obtain social rewards (e.g. positive feedback) features prominently in our lives and relationships, and is relevant to understanding psychopathology - where behavior is often impaired. Investigating social rewards within the psychosis-spectrum offers an especially useful opportunity, given the high rates of impaired social functioning and social isolation. The goal of this study was to investigate hedonic experience associated with social reward processing as a potential biomarker for psychosis risk. This study used a task-based functional magnetic resonance imaging (fMRI) paradigm in adolescents at clinical high-risk for the development of psychosis (CHR, n = 19) and healthy unaffected peers (healthy controls - HC, n = 20). Regional activation and connectivity of the ventromedial prefrontal cortex and ventral striatum were examined in response to receiving positive social feedback relative to an ambiguous feedback condition. Expectations of impaired hedonic processes in CHR youth were generally not supported, as there were no group differences in neural response or task-based connectivity. Although interesting relationships were found linking neural reward response and connectivity with social, anticipatory, and consummatory anhedonia in the CHR group, results are difficult to interpret in light of task limitations. We discuss potential implications for future study designs that seek to investigate social reward processing as a biomarker for psychosis risk.
CognitiveConstruct
RewardProcessing
30,080,060
10.1037/per0000308
2,018
Personality disorders
Personal Disord
A systematic review examining the link between psychopathic personality traits, antisocial behavior, and neural reactivity during reward and loss processing.
Antisocial Behavior (AB) has a tremendous societal cost, motivating investigation of the mechanisms that cause individuals to engage and persist in AB. Recent theories of AB emphasize the role of reward-related neural processes in the etiology of severe and chronic forms of AB, including antisocial personality disorder and psychopathy. However, no systematic reviews have evaluated the hypothesis that reward-related neural dysfunction is an etiologic factor in AB in adult samples. Moreover, it is unclear whether AB is linked to a hyper- or hyposensitive reward system and whether AB is related to neural sensitivity to losses. Thus, the current systematic review examined whether AB (including antisocial personality disorder) and psychopathic traits are related to neural reactivity during reward processing, loss processing, or both. Our review identified seven task-based functional MRI or functional connectivity studies that examined associations between neural response to reward and loss, and dimensional and categorical measures of adult AB and/or psychopathy. Across studies, there was evidence that AB is associated with variability in neural functioning during both reward and loss processing. In particular, impulsive-antisocial traits appeared to be specifically associated with hypersensitivity in the ventral striatum during the anticipation, but not the receipt, of rewards. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
CognitiveConstruct
RewardProcessing
30,078,829
10.2183/pjab.94.020
2,018
Proceedings of the Japan Academy. Series B, Physical and biological sciences
Proc Jpn Acad Ser B Phys Biol Sci
Development of social systems neuroscience using macaques.
This paper reviews the literature on social neuroscience studies using macaques in the hope of encouraging as many researchers as possible to participate in this field of research and thereby accelerate the system-level understanding of social cognition and behavior. We describe how different parts of the primate brain are engaged in different aspects of social information processing, with particular emphasis on the use of experimental paradigms involving more than one monkey in laboratory settings. The description begins with how individual neurons are used for evaluating socially relevant information, such as the identity, face, and focus of attention of others in various social contexts. A description of the neural bases of social reward processing and social action monitoring follows. Finally, we provide several perspectives on novel experimental strategies to help clarify the nature of interacting brains under more socially and ecologically plausible conditions.
CognitiveConstruct
RewardProcessing
30,073,329
10.1001/jamapsychiatry.2018.1973
2,018
JAMA psychiatry
JAMA Psychiatry
Examination of the Neural Basis of Psychoticlike Experiences in Adolescence During Reward Processing.
Psychoticlike experiences (PLEs) are subclinical manifestations of psychotic symptoms and may reflect an increased vulnerability to psychotic disorders. Contemporary models of psychosis propose that dysfunctional reward processing is involved in the cause of these clinical illnesses. To examine the neuroimaging profile of healthy adolescents at 14 and 19 years old points with PLEs, using a reward task. A community-based cohort study, using both a cross-sectional and longitudinal design, was conducted in academic centers in London, Nottingham, United Kingdom, and Dublin, Ireland; Paris, France; and Berlin, Hamburg, Mannheim, and Dresden, Germany. A group of 1434 healthy adolescent volunteers was evaluated, and 2 subgroups were assessed at ages 14 and 19 years. Those who scored as either high or low PLE (based on the upper and lower deciles) on the Community Assessment of Psychic Experiences Questionnaire (CAPE-42) at age 19 years were included in the analysis. The study was conducted from January 1, 2016, to January 1, 2017. Participants were assessed at age 14 and 19 year points using functional magnetic resonance imaging while performing a monetary incentive delay reward task. A first-level model focused on 2 predefined contrasts of anticipation and feedback of a win. The second-level analysis examined activation within the reward network using an a priori-defined region of interest approach. The main effects of group, time, and their interaction on brain activation were examined. Of the 1434 adolescents, 2 groups (n = 149 each) (high PLEs, n = 149, 50 [33.6%] male; low PLEs, n = 149, 84 [56.4%] male) were compared at ages 14 and 19 years. Two regions within the left and right middle frontal gyri showed a main effect of time on brain activation (F1, 93 = 5.559; P = .02; F1, 93 = 5.009; P = .03, respectively); there was no main effect of group. One region within the right middle frontal gyrus demonstrated a significant time × group interaction (F1, 93 = 7.448; P = .01). The findings are consistent with evidence implicating alterations in prefrontal and striatal function during reward processing in the etiology of psychosis. Given the nature of this nonclinical sample this may reflect a combination of aberrant salience yielding abnormal experiences and a compensatory cognitive control mechanism necessary to contextualize them.
CognitiveConstruct
RewardProcessing
30,072,875
10.3389/fnana.2018.00060
2,018
Frontiers in neuroanatomy
Front Neuroanat
The Connectivity Fingerprint of the Human Frontal Cortex, Subthalamic Nucleus, and Striatum.
Within the cortico basal ganglia (BG)-thalamic network, the direct and indirect pathways comprise of projections from the cortex to the striatum (STR), whereas the hyperdirect pathway(s) consist of cortical projections toward the subthalamic nucleus (STN). Each pathway possesses a functionally distinct role for action selection. The current study quantified and compared the structural connectivity between 17 distinct cortical areas with the STN and STR using 7 Tesla diffusion weighted magnetic resonance imaging (dMRI) and resting-state functional MRI (rs-fMRI) in healthy young subjects. The selection of these cortical areas was based on a literature search focusing on animal tracer studies. The results indicate that, relative to other cortical areas, both the STN and STR showed markedly weaker structural connections to areas assumed to be essential for action inhibition such as the inferior frontal cortex pars opercularis. Additionally, the cortical connectivity fingerprint of the STN and STR indicated relatively strong connections to areas related to voluntary motor initiation such as the cingulate motor area and supplementary motor area. Overall the results indicated that the cortical-STN connections were sparser compared to the STR. There were two notable exceptions, namely for the orbitofrontal cortex and ventral medial prefrontal cortex, where a higher tract strength was found for the STN. These two areas are thought to be involved in reward processing and action bias.
CognitiveConstruct
RewardProcessing
30,057,529
10.3389/fnbeh.2018.00134
2,018
Frontiers in behavioral neuroscience
Front Behav Neurosci
Chronic Social Stress Leads to Reduced Gustatory Reward Salience and Effort Valuation in Mice.
Pathology of reward processing is a major clinical feature of stress-related neuropsychiatric disorders including depression. Several dimensions of reward processing can be impacted, including reward valuation/salience, learning, expectancy and effort valuation. To establish the causal relationships between stress, brain changes, and reward processing pathologies, valid animal models are essential. Here, we present mouse experiments investigating behavioral effects of chronic social stress (CSS) in association learning tests of gustatory reward salience and effort valuation. The reward salience test (RST) comprised Pavlovian pairing of a tone with gustatory reward. The effort valuation test (EVT) comprised operant responding for gustatory reinforcement on a progressive ratio schedule (PRS). All testing was conducted with mice at 100% baseline body weight (BBW). In one experiment, mice underwent 15-day CSS or control handling (CON) and testing was conducted using sucrose pellets. In the RST on days 16-17, CSS mice made fewer feeder responses and had a longer tone response latency, than CON mice. In a shallow EVT on days 19-20, CSS mice attained a lower final ratio than CON mice. In a second CSS experiment, mice underwent CSS or CON and testing was conducted with chocolate pellets and in the presence of standard diet (low effort/low reward). In the RST on days 16-18, CSS mice made fewer feeder responses and had a longer tone response latency, than CON mice. In a steep EVT on days 19-20, CSS and CON mice attained less pellets than in the RST, and CSS mice attained a lower final ratio than CON mice. At day 21, blood levels of glucose and the satiety adipokine leptin were similar in CSS and CON mice. Therefore, CSS leads to consistent reductions in reward salience and effort valuation in tests based on association learning. These reward pathology models are being applied to identify the underlying neurobiology and putative molecular targets for therapeutic pharmacology.
CognitiveConstruct
RewardProcessing
30,053,198
10.1093/schbul/sby108
2,019
Schizophrenia bulletin
Schizophr Bull
Rigidity in Motor Behavior and Brain Functioning in Patients With Schizophrenia and High Levels of Apathy.
The aim of this study was to investigate whether apathy in schizophrenia is associated with rigidity in behavior and brain functioning. To this end, we studied associations between variability in dynamic functional connectivity (DFC) in relevant functional brain networks, apathy, and variability in physical activity in schizophrenia. Thirty-one patients with schizophrenia, scoring high on apathy, were included and wore an actigraph. Activity variability was calculated on the activity counts using the root of the Mean Squared Successive Difference (MSSD). Furthermore, we calculated DFC on resting-state data as phase interactions between blood oxygen-level dependent (BOLD) signals of 270 brain regions per volume. Variability (MSSD) in DFC was calculated for 3 networks, including the default-mode network (DMN), frontoparietal network, and salience-reward network (SRN). Finally, we calculated correlations between these DFC estimates and apathy and activity variability. First, lower activity variability was associated with higher levels of apathy. Second, higher levels of apathy were associated with lower variability in DFC in the DMN and SRN. Third, higher activity variability was associated with higher variability in DFC in the SRN. In conclusion, patients with schizophrenia and more severe levels of apathy showed less variability in their physical activity and more rigid functional brain network behavior in the DMN and SRN. These networks have been shown relevant for self-reflection, mental simulation, and reward processing, processes that are pivotal for self-initiated goal-directed behavior. Functional rigidity of these networks may therefore contribute to reduced goal-directed behavior, which is characteristic for these patients.
CognitiveConstruct
RewardProcessing
30,047,755
10.1037/neu0000425
2,018
Neuropsychology
Neuropsychology
Improving motivation through real-time fMRI-based self-regulation of the nucleus accumbens.
Impaired nucleus accumbens (NAcc) activation is associated with amotivation and anhedonia, which are resistant to treatment with antipsychotics and antidepressants in schizophrenia. In this study, healthy participants were trained to self-regulate the activation of their NAcc, a brain region that plays an important role in motivation, using real-time functional magnetic resonance imaging (fMRI) neurofeedback. The experimental group ( = 19) received feedback from the NAcc, whereas the control group ( = 5) received "sham" feedback from the posterior parahippocampal gyrus, a control brain region not normally related to motivation. All participants were trained to use mental strategies to regulate their NAcc activations in a 3T MRI scanner. For the learning effect of NAcc regulation, we found that the majority of participants (74%) in the experimental group successfully learned to self-regulate the NAcc. They also showed improved behavioral performance in motivation and decreased functional connectivity between the NAcc and the ventral medial prefrontal cortex and an increase in small-world properties in the reward circuit after training, indicating improved information integration in reward processing. However, improvement in motivation and modification of function connectivity were not observed in the control group and the participants who failed to self-regulate the NAcc in the experimental group. Self-regulation was influenced by the baseline motivation. These findings suggest that the NAcc could be self-regulated using real-time fMRI neurofeedback and can result in improved motivation in cognitive tasks. (PsycINFO Database Record
CognitiveConstruct
RewardProcessing
30,038,557
10.3389/fnins.2018.00462
2,018
Frontiers in neuroscience
Front Neurosci
Decreased Connection Between Reward Systems and Paralimbic Cortex in Depressive Patients.
Despite decades of research on depression, the underlying pathophysiology of depression remains incompletely understood. Emerging evidence from task-based studies suggests that the abnormal reward-related processing contribute to the development of depression. It is unclear about the function pattern of reward-related circuit during resting state in depressive patients. In present study, seed-based functional connectivity was used to evaluate the functional pattern of reward-related circuit during resting state. Selected seeds were two key nodes in reward processing, medial orbitofrontal cortex (mOFC) and nucleus accumbens (NAcc). Fifty depressive patients and 57 healthy participants were included in present study. Clinical severity of participants was assessed with Hamilton depression scale and Hamilton anxiety scale. We found that compared with healthy participants, depressive patients showed decreased connectivity of right mOFC with left temporal pole (TP_L), right insula extending to superior temporal gyrus (INS_R/STG) and increased connectivity of right mOFC with left precuneus. Similarly, decreased connectivity of left mOFC with TP_L and increased connectivity with cuneus were found in depressive patients. There is also decreased connectivity of right NAcc with bilateral temporal pole, as well as decreased connectivity of left NAcc with INS_R/STG. In addition, the functional connectivity of right nucleus accumbens with right temporal pole (TP_R) was negatively correlated with clinical severity. Our results emphasize the role of communication deficits between reward systems and paralimbic cortex in the pathophysiology of depression.
CognitiveConstruct
RewardProcessing
30,038,315
10.1038/s41598-018-28847-3
2,018
Scientific reports
Sci Rep
Shorter-lived neural taste representations in obese compared to lean individuals.
Previous attempts to uncover a relation between taste processing and weight status have yielded inconclusive results leaving it unclear whether lean and obese individuals process taste differently, and whether group differences reflect differential sensory encoding or evaluative and reward processing. Here, we present the first comparison of dynamic neural processing as assessed by gustatory evoked potentials in obese and lean individuals. Two supra-threshold concentrations of sweet and salty tastants as well as two sizes of blue and green squares were presented to 30 lean (BMI 18.5-25) and 25 obese (BMI > 30) individuals while recording head-surface electroencephalogram (EEG). Multivariate pattern analyses (MVPA) revealed differential taste quality representations from 130 ms until after stimulus offset. Notably, taste representations faded earlier and exhibited a reduced strength in the obese compared to the lean group; temporal generalization analysis indicated otherwise similar taste processing. Differences in later gustatory response patterns even allowed decoding of group membership. Importantly, group differences were absent for visual processing thereby excluding confounding effects from anatomy or signal-to-noise ratio alone. The latency of observed effects is consistent with memory maintenance rather than sensory encoding of taste, thereby suggesting that later evaluative aspects of taste processing are altered in obesity.
CognitiveConstruct
RewardProcessing
30,038,232
10.1038/s41380-018-0122-5
2,019
Molecular psychiatry
Mol Psychiatry
A view behind the mask of sanity: meta-analysis of aberrant brain activity in psychopaths.
Psychopathy is a disorder of high public concern because it predicts violence and offense recidivism. Recent brain imaging studies suggest abnormal brain activity underlying psychopathic behavior. No reliable pattern of altered neural activity has been disclosed so far. This study sought to identify consistent changes of brain activity in psychopaths and to investigate whether these could explain known psychopathology. First, we used activation likelihood estimation (p < 0.05, corrected) to meta-analyze brain activation changes associated with psychopathy across 28 functional magnetic resonance imaging studies reporting 753 foci from 155 experiments. Second, we characterized the ensuing regions functionally by employing metadata of a large-scale neuroimaging database (p < 0.05, corrected). Psychopathy was consistently associated with decreased brain activity in the right laterobasal amygdala, the dorsomedial prefrontal cortex, and bilaterally in the lateral prefrontal cortex. A robust increase of activity was observed in the fronto-insular cortex on both hemispheres. Data-driven functional characterization revealed associations with semantic language processing (left lateral prefrontal and fronto-insular cortex), action execution and pain processing (right lateral prefrontal and left fronto-insular), social cognition (dorsomedial prefrontal cortex), and emotional as well as cognitive reward processing (right amygdala and fronto-insular cortex). Aberrant brain activity related to psychopathy is located in prefrontal, insular, and limbic regions. Physiological mental functions fulfilled by these brain regions correspond to disturbed behavioral patterns pathognomonic for psychopathy. Hence, aberrant brain activity may not just be an epiphenomenon of psychopathy but directly related to the psychopathology of this disorder.
CognitiveConstruct
RewardProcessing
30,026,679
10.3389/fnins.2018.00385
2,018
Frontiers in neuroscience
Front Neurosci
Non-motor Characterization of the Basal Ganglia: Evidence From Human and Non-human Primate Electrophysiology.
Although the basal ganglia have been implicated in a growing list of human behaviors, they include some of the least understood nuclei in the brain. For several decades studies have employed numerous methodologies to uncover evidence pointing to the basal ganglia as a hub of both motor and non-motor function. Recently, new electrophysiological characterization of the basal ganglia in humans has become possible through direct access to these deep structures as part of routine neurosurgery. Electrophysiological approaches for identifying non-motor function have the potential to unlock a deeper understanding of pathways that may inform clinical interventions and particularly neuromodulation. Various electrophysiological modalities can also be combined to reveal functional connections between the basal ganglia and traditional structures throughout the neocortex that have been linked to non-motor behavior. Several reviews have previously summarized evidence for non-motor function in the basal ganglia stemming from behavioral, clinical, computational, imaging, and non-primate animal studies; in this review, instead we turn to electrophysiological studies of non-human primates and humans. We begin by introducing common electrophysiological methodologies for basal ganglia investigation, and then we discuss studies across numerous non-motor domains-emotion, response inhibition, conflict, decision-making, error-detection and surprise, reward processing, language, and time processing. We discuss the limitations of current approaches and highlight the current state of the information.
CognitiveConstruct
RewardProcessing
30,006,604
10.1038/s41398-018-0184-9
2,018
Translational psychiatry
Transl Psychiatry
The major depressive disorder GWAS-supported variant rs10514299 in TMEM161B-MEF2C predicts putamen activation during reward processing in alcohol dependence.
Alcohol dependence (AD) frequently co-occurs with major depressive disorder (MDD). While this comorbidity is associated with an increase in disease burden, worse treatment outcomes, and greater economic costs, the underlying neurobiology remains poorly understood. A recent large-scale GWAS of MDD has identified a locus in the TMEM161B-MEF2C region (rs10514299) as a novel risk variant; however, the biological relevance of this variant has not yet been studied. Given previous reports of disrupted reward processing in both AD and MDD, we hypothesized that rs10514299 would be associated with differences in striatal BOLD responses during reward/loss anticipation in AD. DNA samples from 45 recently detoxified patients with AD and 45 healthy controls (HC) were genotyped for rs10514299. Participants performed the Monetary Incentive Delay task in a 3-Tesla MRI scanner. Effects of rs10514299 on striatal activation during anticipation of high/low reward/loss were investigated. Furthermore, we examined associations between rs10514299 and lifetime AD diagnosis in two independent clinical samples [NIAAA: n = 1858 (1123 cases, 735 controls); SAGE: n = 3838 (1848 cases, 1990 controls)], as well as its association with depression severity in a subsample of individuals with a lifetime AD diagnosis (n = 953). Patients carrying the T allele showed significantly greater putamen activation during anticipation of high reward (p = 0.014), low reward (at trend-level; p = 0.081), high loss (p = 0.024), and low loss (p = 0.046) compared to HCs. Association analyses in the NIAAA sample showed a trend-level relationship between rs10514299 and a lifetime AD diagnosis in the European American subgroup (odds ratio = 0.82, p = 0.09). This finding was not replicated in the SAGE sample. In the NIAAA sample, the T allele was significantly associated with greater depression symptom severity in individuals with a lifetime AD diagnosis (β = 1.25, p = 0.02); this association was driven by the African American ancestry subgroup (β = 2.11, p = 0.008). We show for the first time that the previously identified MDD risk variant rs10514299 in TMEM161B-MEF2C predicts neuronal correlates of reward processing in an AD phenotype, possibly explaining part of the shared pathophysiology and comorbidity between the disorders.
CognitiveConstruct
RewardProcessing
29,992,483
10.3758/s13415-018-0615-3
2,018
Cognitive, affective & behavioral neuroscience
Cogn Affect Behav Neurosci
Electrophysiological measures reveal the role of anterior cingulate cortex in learning from unreliable feedback.
Although a growing number of studies have investigated the neural mechanisms of reinforcement learning, it remains unclear how the brain responds to feedback that is unreliable. A recent theory proposes that the reward positivity (RewP) component of the event-related brain potential (ERP) and frontal midline theta (FMT) power reflect separate feedback-related processing functions of anterior cingulate cortex (ACC). In the present study, the electroencephalogram (EEG) was recorded from participants as they engaged in a time estimation task in which feedback reliability was manipulated across conditions. After each response, they received a cue that indicated that the following feedback stimulus was 100%, 75%, or 50% reliable. The results showed that participants' time estimates adjusted linearly according to the feedback reliability. Moreover, presentation of the cue indicating 100% reliability elicited a larger RewP-like ERP component than the other cues did, and feedback presentation elicited a RewP of approximately equal amplitude for all of the three reliability conditions. By contrast, FMT power elicited by negative feedback decreased linearly from the 100% condition to 75% and 50% condition, and only FMT power predicted behavioral adjustments on the following trials. In addition, an analysis of Beta power and cross-frequency coupling (CFC) of Beta power with FMT phase suggested that Beta-FMT communication modulated motor areas for the purpose of adjusting behavior. We interpreted these findings in terms of the hierarchical reinforcement learning account of ACC, in which the RewP and FMT are proposed to reflect reward processing and control functions of ACC, respectively.
CognitiveConstruct
RewardProcessing
29,990,704
10.1016/j.bandc.2018.07.001
2,018
Brain and cognition
Brain Cogn
The role of the cerebellum for feedback processing and behavioral switching in a reversal-learning task.
Previous studies have reported cerebellar activations during error and reward processing. The present study investigated if the cerebellum differentially processes feedback depending on changes in response strategy during reversal learning, as is conceivable given its internal models for movement and thought. Negative relative to positive feedback in an fMRI-based reversal learning task was hypothesized to be associated with increased cerebellar activations. Moreover, increased activations were expected for negative feedback followed by a change in response strategy compared to negative feedback not followed by such a change, and for first positive feedback after compared to final negative feedback before a change, due to updating of internal models. As predicted, activation in lobules VI and VIIa/Crus I was increased for negative relative to positive feedback, and for final negative feedback before a change in response strategy relative to negative feedback not associated with a change. Moreover, activation was increased for first positive feedback after relative to final negative feedback before a change. These findings are consistent with updating of cerebellar internal models to accommodate new behavioral strategies. Recruitment of posterior regions in reversal learning is in line with the cerebellar functional topography, with posterior regions involved in complex motor and cognitive functions.
CognitiveConstruct
RewardProcessing
29,984,498
10.1002/eat.22886
2,018
The International journal of eating disorders
Int J Eat Disord
Taste sensitivity in anorexia nervosa: A systematic review.
There is evidence for altered processing of taste in anorexia nervosa, particularly in the areas of reward processing and hedonic sensitivity. However, research on whether people with anorexia nervosa identify taste stimuli accurately, known as taste sensitivity, has yielded mixed findings. The objective of this study was to synthesize the literature on taste sensitivity in this disorder to provide a basis for future discussion on whether altered taste sensitivity may be also implicated in wider atypical taste processing in anorexia. Electronic databases were searched systematically to identify published research examining taste sensitivity in anorexia. Search terms were "anorexia nervosa", or "eating disorder", combined with "taste". 18 studies met inclusion criteria. The review of the findings suggest that individuals with AN may experience reduced taste sensitivity that may improve following recovery. However, there was a significant variability in results across studies, potentially reflecting methodological problems including low sample sizes, experimental designs, and uncontrolled confounding variables. This review suggests that altered taste sensitivity could represent a component in the wider altered taste processing observed in anorexia nervosa. However, the heterogeneity of findings highlight the need for future research to consider methodological issues raised by this review.
CognitiveConstruct
RewardProcessing
29,981,291
10.1016/j.neuropsychologia.2018.07.004
2,018
Neuropsychologia
Neuropsychologia
Neural activity to threat in ventromedial prefrontal cortex correlates with individual differences in anxiety and reward processing.
Emotion studies show that ventromedial prefrontal cortex (vmPFC) plays a critical role in negative affect evaluation. Here we investigated two questions: Does the neural sensitivity to threat of bodily harm in vmPFC alter as anxiety levels increase? If the neural sensitivity to threat in vmPFC reflects a kind of general emotional processing, does it predict reward processing? To address these questions, we first recorded participants' self-reported anxiety. In an investigation of neural responses in vmPFC (Session 1), we measured brain activity (fMRI) associated with the anticipation of threat, using a sphere based ROI approach. In a behavioral experiment (Session 2), participants' reward processing efficiency was evaluated when they performed a visual discrimination task in which they had the opportunity to earn cash rewards. We found that across participants, there were tightly coupled associations between signal changes in the vmPFC and self-reported state anxiety. Specifically, participants who showed more activation in vmPFC to threat also exhibited greater behavioral efficiency in reward processing. Path analysis revealed a closely interconnected network of vmPFC (cortical) and VS (ventral striatum, subcortical) which predicted reward processing. Therefore, in addition to negative affect evaluation, neural sensitivity in vmPFC correlated with both anxiety and reward-related metrics. These results support an emerging model in which the vmPFC functions to defend the organism from acute stress and facilitate reward processes.
CognitiveConstruct
RewardProcessing
29,975,170
10.1152/jn.00257.2018
2,018
Journal of neurophysiology
J Neurophysiol
Electrophysiological properties of medium spiny neurons in the nucleus accumbens core of prepubertal male and female Drd1a-tdTomato line 6 BAC transgenic mice.
The nucleus accumbens core (AcbC) is a striatal brain region essential for integrating motivated behavior and reward processing with premotor function. In humans and rodents, research has identified sex differences and sex steroid hormone sensitivity in AcbC-mediated behaviors, in disorders, and in rats in the electrophysiological properties of the AcbC output neuron type, the medium spiny neuron (MSN). It is unknown whether the sex differences detected in MSN electrophysiological properties extend to mice. Furthermore, MSNs come in distinct subtypes with subtle differences in electrophysiological properties, and it is unknown whether MSN subtype-specific electrophysiology varies by sex. To address these questions, we used male and female Drd1a-tdTomato line 6 bacterial artificial chromosome transgenic mice. We made acute brain slices of the AcbC, and performed whole cell patch-clamp recordings across MSN subtypes to comprehensively assess AcbC MSN subtype electrophysiological properties. We found that ( 1 mice MSNs did not exhibit the sex differences detected in rat MSNs, and 2) electrophysiological properties differed between MSN subtypes in both sexes, including rheobase, resting membrane potential, action potential properties, intrinsic excitability, input resistance in both the linear and rectified ranges, and miniature excitatory postsynaptic current properties. These findings significantly extend previous studies of MSN subtypes performed in males or animals of undetermined sex and indicate that the influence of sex upon AcbC MSN properties varies between rodent species. NEW & NOTEWORTHY This research provides the most comprehensive assessment of medium spiny neuron subtype electrophysiological properties to date in a critical brain region, the nucleus accumbens core. It additionally represents the first evaluation of whether mouse medium spiny neuron subtype electrophysiological properties differ by sex.
CognitiveConstruct
RewardProcessing
29,974,560
10.1002/hbm.24273
2,018
Human brain mapping
Hum Brain Mapp
Evidence for a general performance-monitoring system in the human brain.
Adaptive behavior relies on the ability of the brain to form predictions and monitor action outcomes. In the human brain, the same system is thought to monitor action outcomes regardless of whether the information originates from internal (e.g., proprioceptive) and external (e.g., visual) sensory channels. Neural signatures of processing motor errors and action outcomes communicated by external feedback have been studied extensively; however, the existence of such a general action-monitoring system has not been tested directly. Here, we use concurrent EEG-MEG measurements and a probabilistic learning task to demonstrate that event-related responses measured by electroencephalography and magnetoencephalography display spatiotemporal patterns that allow an effective transfer of a multivariate statistical model discriminating the outcomes across the following conditions: (a) erroneous versus correct motor output, (b) negative versus positive feedback, (c) high- versus low-surprise negative feedback, and (d) erroneous versus correct brain-computer-interface output. We further show that these patterns originate from highly-overlapping neural sources in the medial frontal and the medial parietal cortices. We conclude that information about action outcomes arriving from internal or external sensory channels converges to the same neural system in the human brain, that matches this information to the internal predictions.
CognitiveConstruct
RewardProcessing
29,973,873
10.3389/fnhum.2018.00241
2,018
Frontiers in human neuroscience
Front Hum Neurosci
Memory Recall for High Reward Value Items Correlates With Individual Differences in White Matter Pathways Associated With Reward Processing and Fronto-Temporal Communication.
When given a long list of items to remember, people typically prioritize the memorization of the most valuable items. Prior neuroimaging studies have found that cues denoting the presence of high value items can lead to increased activation of the mesolimbic dopaminergic reward circuit, including the nucleus accumbens (NAcc) and ventral tegmental area (VTA), which in turn results in up-regulation of medial temporal lobe encoding processes and better memory for the high value items. Value cues may also trigger the use of elaborative semantic encoding strategies which depend on interactions between frontal and temporal lobe structures. We used diffusion tensor imaging (DTI) to examine whether individual differences in anatomical connectivity within these circuits are associated with value-induced modulation of memory. DTI data were collected from 19 adults who also participated in an functional magnetic resonanceimaging (fMRI) study involving a value-directed memory task. In this task, subjects encoded words with arbitrarily assigned point values and completed free recall tests after each list, showing improved recall performance for high value items. Motivated by our prior fMRI finding of increased recruitment of left-lateralized semantic network regions during the encoding of high value words (Cohen et al., 2014), we predicted that the robustness of the white matter pathways connecting the ventrolateral prefrontal cortex (VLPFC) with the temporal lobe might be a determinant of recall performance for high value items. We found that the mean fractional anisotropy (FA) of each subject's left uncinate fasciculus (UF), a fronto-temporal fiber bundle thought to play a critical role in semantic processing, correlated with the mean number of high value, but not low value, words that subjects recalled. Given prior findings on reward-induced modulation of memory, we also used probabilistic tractography to examine the white matter pathway that links the NAcc to the VTA. We found that the number of fibers projecting from left NAcc to VTA was reliably correlated with subjects' selectivity index, a behavioral measure reflecting the degree to which recall performance was impacted by item value. Together, these findings help to elucidate the neuroanatomical pathways that support verbal memory encoding and its modulation by value.
CognitiveConstruct
RewardProcessing
29,971,685
10.1007/s11682-018-9920-2
2,019
Brain imaging and behavior
Brain Imaging Behav
Altered reward-related neural responses in non-manifesting carriers of the Parkinson disease related LRRK2 mutation.
Disturbances in reward processing occur in Parkinson's disease (PD) however it is unclear whether these are solely drug-related. We applied an event-related fMRI gambling task to a group of non-manifesting carriers (NMC) of the G2019S mutation in the LRRK2 gene, in order to assess the reward network in an "at risk" population for future development of PD. Sixty-eight non-manifesting participants, 32 of which were non-manifesting non-carriers (NMNC), performed a gambling task which included defined intervals of anticipation and response to both reward and punishment in an fMRI setup. Behavior and cerebral activations were measured using both hypothesis driven and whole brain analysis. NMC demonstrated higher trait anxiety scores (p = 0.04) compared to NMNC. Lower activations were detected among NMC during risky anticipation in the left nucleus accumbens (NAcc) (p = 0.05) and during response to punishment in the right insula (p = 0.02), with higher activations among NMC during safe anticipation in the right insula (p = 0.02). Psycho-Physiological Interaction (PPI) analysis from the NAcc and insula revealed differential connectivity patterns. Whole brain analysis demonstrated divergent between-group activations in distributed cortical regions, bilateral caudate, left midbrain, when participants were required to press the response button upon making their next chosen move. Abnormal neural activity in both the reward and motor networks were detected in NMC indicating involvement of the ventral striatum regardless of medication use in "at risk" individuals for future development of PD.
CognitiveConstruct
RewardProcessing
29,951,007
10.3389/fpsyt.2018.00254
2,018
Frontiers in psychiatry
Front Psychiatry
Increased Default Mode Network Connectivity in Obsessive-Compulsive Disorder During Reward Processing.
Obsessive-compulsive disorder (OCD) is characterized by anxiety-provoking, obsessive thoughts (i.e., obsessions) which patients react to with compulsive behaviors (i.e., compulsions). Due to the transient feeling of relief following the reduction of obsession-induced anxiety, compulsions are often described as relieving or even rewarding. Several studies investigated functional activation during reward processing in OCD, but findings are heterogeneous up to now and little is known about potential alterations in functional connectivity. Against this background we studied OCD patients ( = 44) and healthy controls ( = 37) during the receipt of monetary reward by assessing both activation and functional connectivity. Patients showed a decreased activation in several frontal regions and the posterior cingulate (PCC, BA31) together with a stronger connectivity between the PCC and the vmPFC (BA10). Present findings demonstrate an increased connectivity in patients within major nodes of the default mode network (DMN)-a network known to be involved in the evaluation of internal mental states. These results may indicate an increased activity of internal, self-related processing at the expense of a normal responsiveness toward external rewards and incentives. This, in turn, may explain the constant urge for additional reinforcement and patients' inability to inhibit their compulsive behaviors.
CognitiveConstruct
RewardProcessing
29,945,682
10.1186/s13643-018-0749-y
2,018
Systematic reviews
Syst Rev
Effects of neuromodulation on cognitive performance in individuals exhibiting addictive behaviour: a systematic review protocol.
Individuals with substance use and addictive disorders often display greater risk-taking behaviour, higher impulsivity, and altered reward processing compared to individuals without these disorders. While it is not known whether cognitive biases precede or result from addictive behaviour, they likely influence addiction-related decision-making, and may facilitate pathological behaviour. There is evidence that cognitive functions-including those shown to be altered in substance use and addictive disorders-can be influenced by neuromodulation techniques (specifically, transcranial direct current stimulation and transcranial magnetic stimulation). Much of this work has been conducted in healthy populations, however, making it unclear whether these methods can be used effectively to modulate cognitive functioning in individuals with substance use and addictive disorders. The purpose of the current review is to shed light on the potential effectiveness and feasibility of neuromodulation as a means to improve cognitive deficits in substance use disorders. The review will identify and evaluate studies that have examined the effects of transcranial direct current stimulation (tDCS) or transcranial magnetic stimulation (TMS) on cognitive task performance in individuals with chronic substance use or dependence. Relevant studies will be identified through searches in PubMed, PsycINFO, Scopus, and Embase, and narrative review will be used to explore evidence that these techniques can be used successfully to modulate cognitive performance in populations exhibiting addictive behaviour. Assessing individual cognitive domains in turn (e.g. risk-taking, impulsivity, attention), we will critically evaluate the validity and reliability of relevant studies and draw conclusions about the strength of evidence for effective use of neuromodulation in that domain. This protocol is not yet registered with PROSPERO. To determine whether neuromodulation holds promise as an effective treatment for neurocognitive deficits in substance use and addictive disorders, it is essential to look carefully at previous studies using this approach in addiction samples. This review will provide an objective and informative description of what is currently known about the efficacy of these techniques, shed light on the feasibility and potential challenges of using neuromodulation in individuals who exhibit addictive behaviour, and identify the most valuable next steps for future research.
CognitiveConstruct
RewardProcessing
29,944,963
10.1016/j.biopsycho.2018.06.005
2,018
Biological psychology
Biol Psychol
Altered neural inhibition responses to food cues after Roux-en-Y Gastric Bypass.
Roux-en-Y gastric bypass (RYGB) surgery is a highly effective weight-loss intervention that often reduces preference and intake of high-energy foods. Research into the neural mechanisms behind this shift has mainly focused on reward processing of food cues. However, the ability to successfully control food intake and thereby weight-loss also depends on inhibitory control capacity. We investigated whether RYGB leads to alterations in neural inhibitory control in response to food cues. A food-specific go/no-go task with pictures of high-energy (desserts) and low-energy foods (vegetables), was used to assess neural inhibition responses before and after RYGB with functional magnetic resonance imaging. Data from 18 morbidly obese patients (15 females; age 41 ± 11 years; BMI 42 ± 4 kg/m before; BMI 36 ± 4 kg/m after) were analysed. Pre- and post-RYGB BOLD fMRI responses were compared for response inhibition towards high- and low-energy foods. Participants were tested in a satiated state. Response inhibition to high-energy foods was associated with increased activation of the right lateral prefrontal cortex (PFC), right medial PFC, dorsolateral PFC, right middle cingulate cortex and the right inferior frontal operculum (involved in inhibitory control), after compared to before surgery. Response inhibition to low-energy foods elicited diminished post- compared to pre-surgery responses in the left superior temporal pole, right parahippocampal gyrus and right hypothalamus (involved in metabolic control). Neural changes indicate improved response inhibition towards high-energy food cues, altered influence of metabolic control during response inhibition towards low-energy food cues and a more positive attitude to both high-energy and low-energy food after RYGB. Alterations in neural circuits involved in inhibitory control, satiety signalling and reward processing may contribute to effective weight-loss after RYGB.
CognitiveConstruct
RewardProcessing
29,944,859
10.1016/j.physbeh.2018.06.027
2,018
Physiology & behavior
Physiol Behav
Binge-like intake of sucrose reduces the rewarding value of sucrose in adult rats.
Binge eating disorder is the most common eating disorder, but its underlying etiology is poorly understood. Both humans and animals exhibit binge-like intake of highly-palatable food, suggesting that the behavior is driven by the rewarding properties of food, rather than homeostatic signals. Food reward is regulated, in part, by endogenous opioid mechanisms which, themselves, may be altered by excessive eating. We examined this hypothesis by testing whether binge-like sucrose intake modifies the subsequent development of a conditioned place preference (CPP) to sucrose and morphine in both female and male adult rats. Separate groups were given intermittent (12h) or continuous (24 h) access to a sweet solution (10% sucrose or 0.1% saccharin) and food in their home cage over 28 days. Intermittent sucrose access induced binge-like intake, defined as increased consumption within the first hour; importantly, daily sucrose intake was similar for continuous and intermittent access groups. In a later test, all rats developed a conditioned place preference (CPP) to 15% sucrose with the exception of female and male rats given 12-h intermittent access to sucrose. In a separate experiment, all groups displayed a CPP to morphine (4 mg/kg). These findings demonstrate that binge-like sucrose intake, not just increased consumption, disrupts reward processing without affecting stimulus-reward learning. This fits with clinical evidence of hypo-reward responsivity in patients with binge eating disorder.
CognitiveConstruct
RewardProcessing
29,943,173
10.3758/s13415-018-0609-1
2,018
Cognitive, affective & behavioral neuroscience
Cogn Affect Behav Neurosci
The relationship between responsiveness to social and monetary rewards and ADHD symptoms.
Alterations in reward processing are frequently reported in attention deficit hyperactivity disorder (ADHD). One important factor affecting reward processing is the quality of reward as social and monetary rewards are processed by different neural networks. However, the effect of reward type on reward processing in ADHD has not been extensively studied. Hence, in the current study, an exploratory research was conducted to investigate the effect of reward type (i.e., social or monetary) on different phases of reward processing. We recorded event-related potentials (ERPs) during a spatial attention paradigm in which cues heralded availability and type of the upcoming reward and feedbacks informed about the reward earned. Thirty-nine (19 males) healthy individuals (age range: 19-27 years) participated in the study. ADHD symptoms were assessed by using ADHD self-report scale (ASRS). Our results revealed a consistent negative correlation between the hyperactivity subscale of ASRS and almost all social-feedback related ERPs (P2, P3, and FRN). ERP amplitudes after social feedbacks were less positive for P2 and P3 and more negative for FRN for individuals with greater hyperactivity levels. Our findings suggest that hyporesponsiveness to social feedbacks may be associated with hyperactivity. However, the results have to be confirmed with clinical populations.
CognitiveConstruct
RewardProcessing
29,927,688
10.1146/annurev-psych-010418-102936
2,019
Annual review of psychology
Annu Rev Psychol
Stress and Obesity.
Many pathways connect stress and obesity, two highly prevalent problems facing society today. First, stress interferes with cognitive processes such as executive function and self-regulation. Second, stress can affect behavior by inducing overeating and consumption of foods that are high in calories, fat, or sugar; by decreasing physical activity; and by shortening sleep. Third, stress triggers physiological changes in the hypothalamic-pituitary-adrenal axis, reward processing in the brain, and possibly the gut microbiome. Finally, stress can stimulate production of biochemical hormones and peptides such as leptin, ghrelin, and neuropeptide Y. Obesity itself can be a stressful state due to the high prevalence of weight stigma. This article therefore traces the contribution of weight stigma to stress and obesogenic processes, ultimately describing a vicious cycle of stress to obesity to stigma to stress. Current obesity prevention efforts focus solely on eating and exercise; the evidence reviewed in this article points to stress as an important but currently overlooked public policy target.
CognitiveConstruct
RewardProcessing
29,924,634
10.1089/cap.2018.0010
2,018
Journal of child and adolescent psychopharmacology
J Child Adolesc Psychopharmacol
Reward-Based Learning as a Function of Severity of Substance Abuse Risk in Drug-Naïve Youth with ADHD.
Attention-deficit/hyperactivity disorder (ADHD) is associated with elevated risk for later development of substance use disorders (SUD), specifically because youth with ADHD, similar to individuals with SUD, exhibit deficits in learning abilities and reward processing. Another known risk factor for SUD is familial history of substance dependence. Youth with familial SUD history show reward processing deficits, higher prevalence of externalizing disorders, and higher impulsivity scores. Thus, the main objective of this proof-of-concept study is to investigate whether risk loading (ADHD and parental substance use) for developing SUD in drug-naïve youth impacts reward-related learning. Forty-one drug-naïve youth, stratified into three groups: Healthy Controls (HC, n = 13; neither ADHD nor parental SUD), Low Risk (LR, n = 13; ADHD only), and High Risk (HR, n = 15; ADHD and parental SUD), performed a novel Anticipation, Conflict, and Reward (ACR) task. In addition to conventional reaction time (RT) and accuracy analyses, we analyzed computational variables including learning rates and assessed the influence of learned predictions of reward probability and stimulus congruency on RT. The multivariate ANOVA on learning rate, congruence, and prediction revealed a significant main Group effect across these variables [F(3, 37) = 3.79, p = 0.018]. There were significant linear effects for learning rate (Contrast Estimate = 0.181, p = 0.038) and the influence of stimulus congruency on RTs (Contrast Estimate = 1.16, p = 0.017). Post hoc comparisons revealed that HR youth showed the most significant deficits in accuracy and learning rates, while stimulus congruency had a lower impact on RTs in this group. LR youth showed scores between those of the HC and HR youth. These preliminary results suggest that deficits in learning and in adjusting to task difficulty are a function of increasing risk loading for SUD in drug-naïve youth. These results also highlight the importance of developing and applying computational models to study intricate details in behavior that typical analytic methodology may not be sensitive to.
CognitiveConstruct
RewardProcessing
29,921,146
10.1176/appi.ajp.2018.17101124
2,018
The American journal of psychiatry
Am J Psychiatry
Reward Processing in Depression: A Conceptual and Meta-Analytic Review Across fMRI and EEG Studies.
A role for aberrant reward processing in the pathogenesis of depression has long been proposed. However, no review has yet examined its role in depression by integrating conceptual and quantitative findings across functional MRI (fMRI) and EEG methodologies. The authors quantified these effects, with an emphasis on development. A total of 38 fMRI and 12 EEG studies were entered into fMRI and EEG meta-analyses. fMRI studies primarily examined reward anticipation and reward feedback. These were analyzed using the activation likelihood estimation method. EEG studies involved mainly the feedback-related negativity (FRN) event-related potential, and these studies were analyzed using random-effects meta-analysis of the association between FRN and depression. Analysis of fMRI studies revealed significantly reduced striatal activation in depressed compared with healthy individuals during reward feedback. When region-of-interest analyses were included, reduced activation was also observed in reward anticipation, an effect that was stronger in individuals under age 18. FRN was also significantly reduced in depression, with pronounced effects in individuals under age 18. In longitudinal studies, reduced striatal activation in fMRI and blunted FRN in EEG were found to precede the onset of depression in adolescents. Taken together, the findings show consistent neural aberrations during reward processing in depression, namely, reduced striatal signal during feedback and blunted FRN. These aberrations may underlie the pathogenesis of depression and have important implications for development of new treatments.
CognitiveConstruct
RewardProcessing
29,920,950
10.1111/apha.13152
2,019
Acta physiologica (Oxford, England)
Acta Physiol (Oxf)
Dorsal striatum dopamine oscillations: Setting the pace of food anticipatory activity.
Predicting the uncertainties of the ever-changing environment provides a competitive advantage for animals. The need to anticipate food sources has provided a strong evolutionary drive for synchronizing behavioural and internal processes with daily circadian cycles. When food is restricted to a few hours per day, rodents exhibit increased wakefulness and foraging behaviour preceding the arrival of food. Interestingly, while the master clock located in the suprachiasmatic nucleus entrains daily rhythms to the light cycle, it is not necessary for this food anticipatory activity. This suggests the existence of a food-entrained oscillator located elsewhere. Based on the role of nigrostriatal dopamine in reward processing, motor function, working memory and internal timekeeping, we propose a working model by which food-entrained dopamine oscillations in the dorsal striatum can enable animals maintained on a restricted feeding schedule to anticipate food arrival. Finally, we summarize how metabolic signals in the gut are conveyed to the nigrostriatal pathway to suggest possible insight into potential input mechanisms for food anticipatory activity.
CognitiveConstruct
RewardProcessing
29,920,309
10.1016/j.bbr.2018.06.009
2,019
Behavioural brain research
Behav Brain Res
Differential function of medial prefrontal cortex catecholaminergic receptors after long-term sugar consumption.
The medial prefrontal cortex (mPFC) has reciprocal projections with many cerebral structures that are crucial in the control of food ingestion behavior and reward processing; Thus the mPFC has an important function in taste memory recognition. Previous results indicate that long-term consumption of sugar produces changes in appetitive re-learning and suggest that this could trigger an escalating consumption due to the inability to learn new negative consequences related to the same taste. Further evidence suggests that general identity reward value could be encoded in the mPFC. Therefore, the purpose of this study was to evaluate in rats whether after 21 days of sugar consumption the increase in sweet taste preference and latent inhibition of conditioned taste aversion (CTA) were affected differentially by pharmacological activation or blockage of dopaminergic and β-adrenergic receptors, in the mPFC, during CTA acquisition. Results showed that after long-term sugar exposure, mPFC activation of β-adrenergic receptors with clenbuterol delayed aversive memory extinction, but the blockade with propranolol or activation of dopaminergic receptors with apomorphine increased CTA latent inhibition and accelerated aversive memory extinction only after acute sugar exposure. Only dopaminergic blockade with haloperidol prevented sweet taste preference expression after long-term sugar consumption, increased CTA latent inhibition and accelerated extinction after acute sugar exposure. Taken together, the present data provide evidence that catecholaminergic receptors in the mPFC after prolonged sugar consumption underwent functional changes related to re-learning and new aversive taste learning.
CognitiveConstruct
RewardProcessing
29,908,953
10.1016/j.neuropsychologia.2018.06.010
2,019
Neuropsychologia
Neuropsychologia
Electrophysiological indices of anterior cingulate cortex function reveal changing levels of cognitive effort and reward valuation that sustain task performance.
Successful execution of goal-directed behaviors often requires the deployment of cognitive control, which is thought to require cognitive effort. Recent theories have proposed that anterior cingulate cortex (ACC) regulates control levels by weighing the reward-related benefits of control against its effort-related costs. However, given that the sensations of cognitive effort and reward valuation are available only to introspection, this hypothesis is difficult to investigate empirically. We have proposed that two electrophysiological indices of ACC function, frontal midline theta and the reward positivity (RewP), provide objective measures of these functions. To explore this issue, we recorded the electroencephalogram (EEG) from participants engaged in an extended, cognitively-demanding task. Participants performed a time estimation task for 2 h in which they received reward and error feedback according to their task performance. We observed that the amplitude of the RewP, a feedback-locked component of the event related brain potential associated with reward processing, decreased with time-on-task. Conversely, frontal midline theta power, which consists of 4-8 Hz EEG oscillations associated with cognitive effort, increased with time-on-task. We also explored how these phenomena changed over time by conducting within-participant multi-level modeling analyses. Our results suggest that extended execution of a cognitively-demanding task is characterized by an early phase in which high control levels foster rapid improvements in task performance, and a later phase in which high control levels were necessary to maintain stable task performance, perhaps counteracting waning reward valuation.
CognitiveConstruct
RewardProcessing
29,906,489
10.1016/j.appet.2018.06.009
2,018
Appetite
Appetite
Taste at first (person) sight: Visual perspective modulates brain activity implicitly associated with viewing unhealthy but not healthy foods.
Every day, people are exposed to images of appetizing foods that can lead to high-calorie intake and contribute to overweight and obesity. Research has documented that manipulating the visual perspective from which eating is viewed helps resist temptation by altering the appraisal of unhealthy foods. However, the neural basis of this effect has not yet been examined using neuroimaging methods. Moreover, it is not known whether the benefits of this strategy can be observed when people, especially overweight, are not explicitly asked to imagine themselves eating. Last, it remains to be investigated if visual perspective could be used to promote healthy foods. The present work manipulated camera angles and tested whether visual perspective modulates activity in brain regions associated with taste and reward processing while participants watch videos featuring a hand grasping (unhealthy or healthy) foods from a plate during functional magnetic resonance imagining (fMRI). The plate was filmed from the perspective of the participant (first-person perspective; 1PP), or from a frontal view as if watching someone else eating (third-person perspective; 3PP). Our findings reveal that merely viewing unhealthy food cues from a 1PP (vs. 3PP) increases activity in brain regions that underlie representations of rewarding (appetitive) experiences (amygdala) and food intake (superior parietal gyrus). Additionally, our results show that ventral striatal activity is positively correlated with body mass index (BMI) during exposure to unhealthy foods from a 1PP (vs. 3PP). These findings suggest that unhealthy foods should be promoted through third-person (video) images to weaken the reward associated with their simulated consumption, especially amongst overweight people. It appears however that, as such, manipulating visual perspective fails to enhance the perception of healthy foods. Their promotion thus requires complementary solutions.
CognitiveConstruct
RewardProcessing
29,898,209
10.1001/jamapsychiatry.2018.1100
2,018
JAMA psychiatry
JAMA Psychiatry
Evaluation of the Social Motivation Hypothesis of Autism: A Systematic Review and Meta-analysis.
The social motivation hypothesis posits that individuals with autism spectrum disorder (ASD) find social stimuli less rewarding than do people with neurotypical activity. However, functional magnetic resonance imaging (fMRI) studies of reward processing have yielded mixed results. To examine whether individuals with ASD process rewarding stimuli differently than typically developing individuals (controls), whether differences are limited to social rewards, and whether contradictory findings in the literature might be due to sample characteristics. Articles were identified in PubMed, Embase, and PsycINFO from database inception until June 1, 2017. Functional MRI data from these articles were provided by most authors. Publications were included that provided brain activation contrasts between a sample with ASD and controls on a reward task, determined by multiple reviewer consensus. When fMRI data were not provided by authors, multiple reviewers extracted peak coordinates and effect sizes from articles to recreate statistical maps using seed-based d mapping software. Random-effects meta-analyses of responses to social, nonsocial, and restricted interest stimuli, as well as all of these domains together, were performed. Secondary analyses included meta-analyses of wanting and liking, meta-regression with age, and correlations with ASD severity. All procedures were conducted in accordance with Meta-analysis of Observational Studies in Epidemiology guidelines. Brain activation differences between groups with ASD and typically developing controls while processing rewards. All analyses except the domain-general meta-analysis were planned before data collection. The meta-analysis included 13 studies (30 total fMRI contrasts) from 259 individuals with ASD and 246 controls. Autism spectrum disorder was associated with aberrant processing of both social and nonsocial rewards in striatal regions and increased activation in response to restricted interests (social reward, caudate cluster: d = -0.25 [95% CI, -0.41 to -0.08]; nonsocial reward, caudate and anterior cingulate cluster: d = -0.22 [95% CI, -0.42 to -0.02]; restricted interests, caudate and nucleus accumbens cluster: d = 0.42 [95% CI, 0.07 to 0.78]). Individuals with ASD show atypical processing of social and nonsocial rewards. Findings support a broader interpretation of the social motivation hypothesis of ASD whereby general atypical reward processing encompasses social reward, nonsocial reward, and perhaps restricted interests. This meta-analysis also suggests that prior mixed results could be driven by sample age differences, warranting further study of the developmental trajectory for reward processing in ASD.
CognitiveConstruct
RewardProcessing
29,897,026
10.1017/S003329171800140X
2,019
Psychological medicine
Psychol Med
Learning to trust: social feedback normalizes trust behavior in first-episode psychosis and clinical high risk.
Psychosis is characterized by problems in social functioning that exist well before illness onset, and in individuals at clinical high risk (CHR) for psychosis. Trust is an essential element for social interactions that is impaired in psychosis. In the trust game, chronic patients showed reduced baseline trust, impaired response to positive social feedback, and attenuated brain activation in reward and mentalizing areas. We investigated whether first-episode psychosis patients (FEP) and CHR show similar abnormalities in the neural and behavioral mechanisms underlying trust. Twenty-two FEP, 17 CHR, and 43 healthy controls performed two trust games, with a cooperative and an unfair partner in the fMRI scanner. Region of interest analyses were performed on mentalizing and reward processing areas, during the investment and outcome phases of the games. Compared with healthy controls, FEP and CHR showed reduced baseline trust, but like controls, learned to trust in response to cooperative and unfair feedback. Symptom severity was not associated with baseline trust, however in FEP associated with reduced response to feedback. The only group differences in brain activation were that CHR recruited the temporo-parietal junction (TPJ) more than FEP and controls during investment in the unfair condition. This hyper-activation in CHR was associated with greater symptom severity. Reduced baseline trust may be associated with risk for psychotic illness, or generally with poor mental health. Feedback learning is still intact in CHR and FEP, as opposed to chronic patients. CHR however show distinct neural activation patterns of hyper-activation of the TPJ.
CognitiveConstruct
RewardProcessing
29,894,825
10.1016/j.neuroimage.2018.06.032
2,018
NeuroImage
Neuroimage
Added value of money on motor performance feedback: Increased left central beta-band power for rewards and fronto-central theta-band power for punishments.
Monetary rewards and punishments have been shown to respectively enhance retention of motor memories and short-term motor performance, but their underlying neural bases in the context of motor control tasks remain unclear. Using electroencephalography (EEG), the present study tested the hypothesis that monetary rewards and punishments are respectively reflected in post-feedback beta-band (20-30 Hz) and theta-band (3-8 Hz) oscillatory power. While participants performed upper limb reaching movements toward visual targets using their right hand, the delivery of monetary rewards and punishments was manipulated as well as their probability (i.e., by changing target size). Compared to unrewarded and unpunished trials, monetary rewards and the successful avoidance of punishments both entailed greater beta-band power at left central electrodes overlaying contralateral motor areas. In contrast, monetary punishments and reward omissions both entailed increased theta-band power at fronto-central scalp sites. Additional analyses revealed that beta-band power was further increased when rewards were lowly probable. In light of previous work demonstrating similar beta-band modulations in basal ganglia during reward processing, the present results may reflect functional communication of reward-related information between the basal ganglia and motor cortical regions. In turn, the increase in fronto-central theta-band power after monetary punishments may reflect an emphasized cognitive need for behavioral adjustments. Globally, the present work identifies possible neural substrates for the growing behavioral evidence showing beneficial effects of monetary feedback on motor learning and performance.
CognitiveConstruct
RewardProcessing
29,890,186
10.1016/j.appet.2018.06.014
2,018
Appetite
Appetite
Is brain response to food rewards related to overeating? A test of the reward surfeit model of overeating in children.
The reward surfeit model of overeating suggests that heightened brain response to rewards contributes to overeating and subsequent weight gain. However, previous studies have not tested whether brain response to reward is associated with food intake, particularly during childhood, a period of dynamic development in reward and inhibitory control neurocircuitry. We conducted functional magnetic resonance imaging (fMRI) with 7-11-year-old children (n = 59; healthy weight, n = 31; overweight, n = 28; 54% female) while they played a modified card-guessing paradigm to examine blood-oxygen-level-dependent (BOLD) response to anticipating and winning rewards (food, money, neutral). Food intake was assessed at three separate meals that measured different facets of eating behavior: 1) typical consumption (baseline), 2) overindulgence (palatable buffet), and 3) eating in the absence of hunger (EAH). A priori regions of interest included regions implicated in both reward processing and inhibitory control. Multiple stepwise regressions were conducted to examine the relationship between intake and BOLD response to rewards. Corrected results showed that a greater BOLD response in the medial prefrontal cortex for anticipating food compared to money positively correlated with how much children ate at the baseline and palatable buffet meals. BOLD response in the dorsolateral prefrontal cortex for winning food compared to money was positively correlated with intake at the palatable buffet meal and EAH. All aforementioned relationships were independent of child weight status. Findings support the reward surfeit model by showing that increased brain response to food compared to money rewards positively correlates with laboratory measures of food intake in children.
CognitiveConstruct
RewardProcessing
29,888,833
10.1111/pcn.12689
2,018
Psychiatry and clinical neurosciences
Psychiatry Clin Neurosci
Just-in-time response to reward as a function of ADHD symptom severity.
Attention-deficit hyperactivity disorder (ADHD) neuroimaging studies have identified substantial differences in reward-related circuits on a trial-by-trial basis. However, no research to date has evaluated the effect of motivational context on neural activity in settings with intermittent reward in ADHD. The present study was designed to identify neural processes underlying both immediate effects of reward and sustained effects of reward associated with motivational context in adult ADHD patients. We used a functional magnetic resonance imaging paradigm, including a time estimation task with constant versus intermittent reward conditions, in a sample of 21 medication-naïve adults with combined ADHD and 24 healthy adults. Although no between-group neural differences were detected, orbitofrontal activity dropped in association with high ADHD symptom severity during the transition from initial non-reward context blocks to subsequent reward context blocks. In turn, ADHD symptom severity predicted higher orbitofrontal activity in response to immediate reward versus no reward within reward context blocks. These results suggest that high ADHD symptom severity scorers adopted a 'just-in-time' strategy, involving the recruitment of reward processing brain areas in the face of immediate reward rather than a sustained response to motivational context.
CognitiveConstruct
RewardProcessing
29,888,303
10.1016/j.ynstr.2018.01.004
2,018
Neurobiology of stress
Neurobiol Stress
Chronic social stress induces peripheral and central immune activation, blunted mesolimbic dopamine function, and reduced reward-directed behaviour in mice.
Psychosocial stress is a major risk factor for depression, stress leads to peripheral and central immune activation, immune activation is associated with blunted dopamine (DA) neural function, DA function underlies reward interest, and reduced reward interest is a core symptom of depression. These states might be inter-independent in a complex causal pathway. Whilst animal-model evidence exists for some specific steps in the pathway, there is currently no animal model in which it has been demonstrated that social stress leads to each of these immune, neural and behavioural states. Such a model would provide important existential evidence for the complex pathway and would enable the study of causality and mediating mechanisms at specific steps in the pathway. Therefore, in the present mouse study we investigated for effects of 15-day resident-intruder chronic social stress (CSS) on each of these states. Relative to controls, CSS mice exhibited higher spleen levels of granulocytes, inflammatory monocytes and T helper 17 cells; plasma levels of inducible nitric oxide synthase; and liver expression of genes encoding kynurenine pathway enzymes. CSS led in the ventral tegmental area to higher levels of kynurenine and the microglia markers Iba1 and and higher binding activity of DA D1 receptor; and in the nucleus accumbens (NAcc) to higher kynurenine, lower DA turnover and lower expression. Pharmacological challenge with DA reuptake inhibitor identified attenuation of DA stimulatory effects on locomotor activity and NAcc expression in CSS mice. In behavioural tests of operant responding for sucrose reward validated as sensitive assays for NAcc DA function, CSS mice exhibited less reward-directed behaviour. Therefore, this mouse study demonstrates that a chronic social stressor leads to changes in each of the immune, neural and behavioural states proposed to mediate between stress and disruption of DA-dependent reward processing. The model can now be applied to investigate causality and, if demonstrated, underlying mechanisms in specific steps of this immune-neural-behavioural pathway, and thereby to identify potential therapeutic targets.
CognitiveConstruct
RewardProcessing
29,885,086
10.1002/hbm.24224
2,018
Human brain mapping
Hum Brain Mapp
Aerobic exercise modulates anticipatory reward processing via the μ-opioid receptor system.
Physical exercise modulates food reward and helps control body weight. The endogenous µ-opioid receptor (MOR) system is involved in rewarding aspects of both food and physical exercise, yet interaction between endogenous opioid release following exercise and anticipatory food reward remains unresolved. Here we tested whether exercise-induced opioid release correlates with increased anticipatory reward processing in humans. We scanned 24 healthy lean men after rest and after a 1 h session of aerobic exercise with positron emission tomography (PET) using MOR-selective radioligand [ C]carfentanil. After both PET scans, the subjects underwent a functional magnetic resonance imaging (fMRI) experiment where they viewed pictures of palatable versus nonpalatable foods to trigger anticipatory food reward responses. Exercise-induced changes in MOR binding in key regions of reward circuit (amygdala, thalamus, ventral and dorsal striatum, and orbitofrontal and cingulate cortices) were used to predict the changes in anticipatory reward responses in fMRI. Exercise-induced changes in MOR binding correlated negatively with the exercise-induced changes in neural anticipatory food reward responses in orbitofrontal and cingulate cortices, insula, ventral striatum, amygdala, and thalamus: higher exercise-induced opioid release predicted higher brain responses to palatable versus nonpalatable foods. We conclude that MOR activation following exercise may contribute to the considerable interindividual variation in food craving and consumption after exercise, which might promote compensatory eating and compromise weight control.
CognitiveConstruct
RewardProcessing
29,873,614
10.1152/jn.00167.2018
2,018
Journal of neurophysiology
J Neurophysiol
Effects of nidopallium caudolaterale inactivation on serial-order behavior in pigeons ( Columba livia).
Serial-order behavior is the ability to complete a sequence of responses in a predetermined order to achieve a reward. In birds, serial-order behavior is thought to be impaired by damage to the nidopallium caudolaterale (NCL). In the current study, we examined the role of the NCL in serial-order behavior by training pigeons on a 4-item serial-order task and a go/no-go discrimination task. Following training, pigeons received infusions of 1 μl of either tetrodotoxin (TTX) or saline. Saline infusions had no impact on serial-order behavior, whereas TTX infusions resulted in a significant decrease in performance. The serial-order impairments, however, were not the result of any specific error at any specific list item. With respect to the go/no-go discrimination task, saline infusions also had no impact on performance, whereas TTX infusions impaired pigeons' discrimination abilities. Given the impairments on the go/no-go discrimination task, which does not require processing of serial-order information, we tentatively conclude that damage to the NCL does not impair serial-order behavior per se, but rather results in a more generalized impairment that may impact performance across a range of tasks. NEW & NOTEWORTHY We examined the role of the nidopallium caudolaterale (NCL) in serial-order behavior by training pigeons on a 4-item serial-order task and selectively inhibiting the region with TTX. Although TTX infusions did impair serial-order behavior, the pattern of the deficit, plus the fact that TTX also impaired performance on a task without a serial-order component, indicates that inactivation of NCL causes impairments in reward processing or inhibition rather than serial-order behavior.
CognitiveConstruct
RewardProcessing
29,859,556
10.1016/j.jaac.2018.03.012
2,018
Journal of the American Academy of Child and Adolescent Psychiatry
J Am Acad Child Adolesc Psychiatry
Preschool- and School-Age Irritability Predict Reward-Related Brain Function.
Although chronic irritability in childhood is prevalent, impairing, and predictive of later maladjustment, its pathophysiology is largely unknown. Deficits in reward processing are hypothesized to play a role in irritability. The current study aimed to identify how the developmental timing of irritability during preschool- and school-age relates to reward-related brain function during school-age. Children's irritability was assessed during the preschool period (wave 1; ages 3.0-5.9 years) and 3 years later (wave 2; ages 5.9-9.6 years) using a clinical interview. At wave 2, children (N = 46; 28 female and 18 male) performed a monetary incentive delay task in which they received rewards, if they successfully hit a target, or no reward regardless of performance, during functional magnetic resonance imaging. Children with more versus less severe preschool irritability, controlling for concurrent irritability, exhibited altered reward-related connectivity: right amygdala with insula and inferior parietal lobe as well as left ventral striatum with lingual gyrus, postcentral gyrus, superior parietal lobe, and culmen. Children with more versus less severe concurrent irritability, controlling for preschool irritability, exhibited a similar pattern of altered connectivity between left and right amygdalae and superior frontal gyrus and between left ventral striatum and precuneus and culmen. Neural differences associated with irritability were most evident between reward and no-reward conditions when participants missed the target. Preschool-age irritability and concurrent irritability were uniquely associated with aberrant patterns of reward-related connectivity, highlighting the importance of developmental timing of irritability for brain function.
CognitiveConstruct
RewardProcessing
29,851,251
10.1111/1749-4877.12340
2,018
Integrative zoology
Integr Zool
Eating as a motivated behavior: modulatory effect of high fat diets on energy homeostasis, reward processing and neuroinflammation.
Eating is a basic motivated behavior that provides fuel for the body and supports brain function. To ensure survival, the brain's feeding circuits are tuned to monitor peripheral energy balance and promote food-seeking behavior when energy stores are low. The brain's bias toward a positive energy state, which is necessary to ensure adequate nutrition during times of food scarcity, is evolutionarily conserved across mammalian species and is likely to drive overeating in the presence of a palatable, energy-dense diet. Animal models of diet-induced overeating have played a vital role in investigating how the drive to consume palatable food may override the homeostatic processes that serve to maintain energy balance. These animal models have provided valuable insights into the neurobiological mechanisms underlying homeostatic and non-homeostatic eating, motivation and food reward, and the development of obesity and related comorbidities. Here, we provide a brief review of this literature and discuss how diet-induced inflammation in the central nervous system impacts the neural control of food intake and regulation of body weight. The connection between diet and the immune system provides an exciting new direction for the study of ingestive behavior and the pathophysiology of obesity.
CognitiveConstruct
RewardProcessing
29,844,476
10.1038/s41386-018-0094-9
2,018
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
Neuropsychopharmacology
Not worth the wait: cocaine alters reward processing in the nucleus accumbens.
null
CognitiveConstruct
RewardProcessing
29,809,046
10.1037/bne0000244
2,018
Behavioral neuroscience
Behav Neurosci
Exposure to bright light biases effort-based decisions.
Secreted in the evening and the night, melatonin suppresses activity of the mesolimbic dopamine pathway, a brain pathway involved in reward processing. However, exposure to bright light diminishes-or even prevents-melatonin secretion. Thus, we hypothesized that reward processing, in the evening, is more pronounced in bright light (vs. dim light). Healthy human participants carried out three tasks that tapped into various aspects of reward processing (effort expenditure for rewards task [EEfRT]; two-armed bandit task [2ABT]; balloon analogue risk task [BART). Brightness was manipulated within-subjects (bright vs. dim light), in separate evening sessions. During the EEfRT, participants used reward-value information more strongly when they were exposed to bright light (vs. dim light). This finding supported our hypothesis. However, exposure to bright light did not significantly affect task behavior on the 2ABT and the BART. While future research is necessary (e.g., to zoom in on working mechanisms), these findings have potential implications for the design of physical work environments. (PsycINFO Database Record
CognitiveConstruct
RewardProcessing
29,807,846
10.1016/j.euroneuro.2018.04.001
2,018
European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology
Eur Neuropsychopharmacol
Characterizing decision-making and reward processing in bipolar disorder: A cluster analysis.
The presence of abnormalities in emotional decision-making and reward processing among bipolar patients (BP) has been well rehearsed. These disturbances are not limited to acute phases and are common even during remission. In recent years, the existence of discrete cognitive profiles in this psychiatric population has been replicated. However, emotional decision making and reward processing domains have barely been studied. Therefore, our aim was to explore the existence of different profiles on the aforementioned cognitive dimensions in BP. The sample consisted of 126 euthymic BP. Main sociodemographic, clinical, functioning, and neurocognitive variables were gathered. A hierarchical-clustering technique was used to identify discrete neurocognitive profiles based on the performance in the Iowa Gambling Task. Afterward, the resulting clusters were compared using ANOVA or Chi-squared Test, as appropriate. Evidence for the existence of three different profiles was provided. Cluster 1 was mainly characterized by poor decision ability. Cluster 2 presented the lowest sensitivity to punishment. Finally, cluster 3 presented the best decision-making ability and the highest levels of punishment sensitivity. Comparison between the three clusters indicated that cluster 2 was the most functionally impaired group. The poorest outcomes in attention, executive function domains, and social cognition were also observed within the same group. In conclusion, similarly to that observed in "cold cognitive" domains, our results suggest the existence of three discrete cognitive profiles concerning emotional decision making and reward processing. Amongst all the indexes explored, low punishment sensitivity emerge as a potential correlate of poorer cognitive and functional outcomes in bipolar disorder.
CognitiveConstruct
RewardProcessing
29,797,564
10.1111/acer.13781
2,018
Alcoholism, clinical and experimental research
Alcohol Clin Exp Res
Stress, Motivation, and the Gut-Brain Axis: A Focus on the Ghrelin System and Alcohol Use Disorder.
Since its discovery, the gut hormone, ghrelin, has been implicated in diverse functional roles in the central nervous system. Central and peripheral interactions between ghrelin and other hormones, including the stress-response hormone cortisol, govern complex behavioral responses to external cues and internal states. By acting at ventral tegmental area dopaminergic projections and other areas involved in reward processing, ghrelin can induce both general and directed motivation for rewards, including craving for alcohol and other alcohol-seeking behaviors. Stress-induced increases in cortisol seem to increase ghrelin in the periphery, suggesting a pathway by which ghrelin influences how stressful life events trigger motivation for rewards. However, in some states, ghrelin may be protective against the anxiogenic effects of stressors. This critical review brings together a dynamic and growing literature, that is, at times inconsistent, on the relationships between ghrelin, central reward-motivation pathways, and central and peripheral stress responses, with a special focus on its emerging role in the context of alcohol use disorder.
CognitiveConstruct
RewardProcessing
29,796,839
10.1007/7854_2018_51
2,018
Current topics in behavioral neurosciences
Curr Top Behav Neurosci
Does Anhedonia Presage Increased Risk of Posttraumatic Stress Disorder? : Adolescent Anhedonia and Posttraumatic Disorders.
Anhedonia, the reduced ability to experience pleasure, is a dimensional entity linked to multiple neuropsychiatric disorders, where it is associated with diminished treatment response, reduced global function, and increased suicidality. It has been suggested that anhedonia and the related disruption in reward processing may be critical precursors to development of psychiatric symptoms later in life. Here, we examine cross-species evidence supporting the hypothesis that early life experiences modulate development of reward processing, which if disrupted, result in anhedonia. Importantly, we find that anhedonia may confer risk for later neuropsychiatric disorders, especially posttraumatic stress disorder (PTSD). Whereas childhood trauma has long been associated with increased anhedonia and increased subsequent risk for trauma-related disorders in adulthood, here we focus on an additional novel, emerging direct contributor to anhedonia in rodents and humans: fragmented, chaotic environmental signals ("FRAG") during critical periods of development. In rodents, recent data suggest that adolescent anhedonia may derive from aberrant pleasure/reward circuit maturation. In humans, recent longitudinal studies support that FRAG is associated with increased anhedonia in adolescence. Both human and rodent FRAG exposure also leads to aberrant hippocampal function. Prospective studies are underway to examine if anhedonia is also a marker of PTSD risk. These preliminary cross-species studies provide a critical construct for future examination of the etiology of trauma-related symptoms in adults and for and development of prophylactic and therapeutic interventions. In addition, longitudinal studies of reward circuit development with and without FRAG will be critical to test the mechanistic hypothesis that early life FRAG modifies reward circuitry with subsequent consequences for adolescent-emergent anhedonia and contributes to risk and resilience to trauma and stress in adulthood.
CognitiveConstruct
RewardProcessing
29,790,868
10.1097/j.pain.0000000000001232
2,018
Pain
Pain
Altered prefrontal correlates of monetary anticipation and outcome in chronic pain.
Chronic pain may alter both affect- and value-related behaviors, which represents a potentially treatable aspect of chronic pain experience. Current understanding of how chronic pain influences the function of brain reward systems, however, is limited. Using a monetary incentive delay task and functional magnetic resonance imaging (fMRI), we measured neural correlates of reward anticipation and outcomes in female participants with the chronic pain condition of fibromyalgia (N = 17) and age-matched, pain-free, female controls (N = 15). We hypothesized that patients would demonstrate lower positive arousal, as well as altered reward anticipation and outcome activity within corticostriatal circuits implicated in reward processing. Patients demonstrated lower arousal ratings as compared with controls, but no group differences were observed for valence, positive arousal, or negative arousal ratings. Group fMRI analyses were conducted to determine predetermined region of interest, nucleus accumbens (NAcc) and medial prefrontal cortex (mPFC), responses to potential gains, potential losses, reward outcomes, and punishment outcomes. Compared with controls, patients demonstrated similar, although slightly reduced, NAcc activity during gain anticipation. Conversely, patients demonstrated dramatically reduced mPFC activity during gain anticipation-possibly related to lower estimated reward probabilities. Further, patients demonstrated normal mPFC activity to reward outcomes, but dramatically heightened mPFC activity to no-loss (nonpunishment) outcomes. In parallel to NAcc and mPFC responses, patients demonstrated slightly reduced activity during reward anticipation in other brain regions, which included the ventral tegmental area, anterior cingulate cortex, and anterior insular cortex. Together, these results implicate altered corticostriatal processing of monetary rewards in chronic pain.
CognitiveConstruct
RewardProcessing
29,779,745
10.1016/bs.pbr.2018.03.017
2,018
Progress in brain research
Prog Brain Res
The impact of visual art and emotional sounds in specific musical anhedonia.
A small percentage of healthy individuals do not find music pleasurable, a condition known as specific musical anhedonia. These individuals have no impairment in music perception which might account for their anhedonia; their sensitivity to primary and secondary rewards is also preserved, and they do not show generalized depression. However, it is still unclear whether this condition is entirely specific to music, or rather reflects a more general deficit in experiencing pleasure, either from aesthetic rewards in general, or in response to other types of emotional sounds. The aim of this study is to determine whether individuals with specific musical anhedonia also show blunted emotional responses from other aesthetic rewards or emotional acoustic stimuli different than music. In two tasks designed to assess sensitivity to visual art and emotional sounds, we tested 13 individuals previously identified as specific musical anhedonics, together with two more groups with average (musical hedonic, HDN) and high (musical hyperhedonics, HHDN) sensitivity to experience reward from music. Differences among groups in skin conductance response and behavioral measures in response to pleasantness were analyzed in both tasks. Notably, specific musical anhedonics showed similar hedonic reactions, both behaviorally and physiologically, as the HDN control group in both tasks. These findings suggest that music hedonic sensitivity might be distinct from other human abstract reward processing and from an individual's ability to experience emotion from emotional sounds. The present results highlight the possible existence of specific neural pathways involved in the capacity to experience reward in music-related activities.
CognitiveConstruct
RewardProcessing
29,777,827
10.1016/j.neuroimage.2018.05.039
2,018
NeuroImage
Neuroimage
Is the encoding of Reward Prediction Error reliable during development?
Reward Prediction Errors (RPEs), defined as the difference between the expected and received outcomes, are integral to reinforcement learning models and play an important role in development and psychopathology. In humans, RPE encoding can be estimated using fMRI recordings, however, a basic measurement property of RPE signals, their test-retest reliability across different time scales, remains an open question. In this paper, we examine the 3-month and 3-year reliability of RPE encoding in youth (mean age at baseline = 10.6 ± 0.3 years), a period of developmental transitions in reward processing. We show that RPE encoding is differentially distributed between the positive values being encoded predominantly in the striatum and negative RPEs primarily encoded in the insula. The encoding of negative RPE values is highly reliable in the right insula, across both the long and the short time intervals. Insula reliability for RPE encoding is the most robust finding, while other regions, such as the striatum, are less consistent. Striatal reliability appeared significant as well once covarying for factors, which were possibly confounding the signal to noise ratio. By contrast, task activation during feedback in the striatum is highly reliable across both time intervals. These results demonstrate the valence-dependent differential encoding of RPE signals between the insula and striatum, and the consistency of RPE signals or lack thereof, during childhood and into adolescence. Characterizing the regions where the RPE signal in BOLD fMRI is a reliable marker is key for estimating reward-processing alterations in longitudinal designs, such as developmental or treatment studies.
CognitiveConstruct
RewardProcessing
29,760,181
10.1523/JNEUROSCI.2540-17.2018
2,018
The Journal of neuroscience : the official journal of the Society for Neuroscience
J Neurosci
Corticosterone Signaling and a Lateral Habenula-Ventral Tegmental Area Circuit Modulate Compulsive Self-Injurious Behavior in a Rat Model.
Self-injurious behavior (SIB) is commonly observed in patients with neuropsychiatric disorders, as well as in nonclinical populations with stress-related mental-health problems. However, the exact circuitry mechanisms underlying SIB have remained poorly understood. Here, with bilateral injection of muscimol into the entopeduncular nucleus (EP), we established a rat model of SIB. Following the muscimol injection, the male rats exhibited in a dose-dependent manner stereotypic self-biting behavior that lasted for hours and often resulted in wounds of various severities. The SIB was associated with an elevated level of serum corticosterone and could be exacerbated by enhancing the corticosterone signaling and, conversely, alleviated by inhibiting the corticosterone signaling. Activity mapping using c-fos immunostaining, combined with connectivity mapping using herpes simplex virus-based anterograde tracing from the EP and pseudorabies virus-based retrograde tracing from the masseter muscle, revealed the potential involvement of many brain areas in SIB. In particular, the lateral habenula (LHb) and the ventral tegmental area (VTA), the two connected brain areas involved in stress response and reward processing, showed a significant increase in neuronal activation during SIB. Furthermore, suppressing the LHb activity or modulating the GABAergic transmission in the VTA could significantly reduce the occurrence of SIB. These results demonstrate the importance of stress hormone signaling and the LHb-VTA circuit in modulating SIB resulting from EP malfunction, and suggest potential targets for therapeutic intervention of SIB and related disorders. Self-injurious behavior (SIB) occurs in ∼4% of the general population, with substantially higher occurrence among adolescents and patients of neuropsychiatric disorders. Stress has been linked to the occurrence of SIB, yet the underlying mechanisms have remained unclear. Using a rat model of SIB induced by disruption of activity in the entopeduncular nucleus (EP), we found that the behavior is regulated by stress and linked to corticosterone signaling. Viral tracing and c-fos immunostaining revealed the involvement of various subcortical areas, especially the EP-lateral habenula (LHb)-ventral tegmental area (VTA) circuit, in SIB. Furthermore, regulating activity in the LHb or the VTA alleviates SIB. These results may have implications in the development of new strategies for treating SIB.
CognitiveConstruct
RewardProcessing
29,759,821
10.1016/j.bpsc.2018.04.003
2,018
Biological psychiatry. Cognitive neuroscience and neuroimaging
Biol Psychiatry Cogn Neurosci Neuroimaging
Using Multilevel Modeling to Examine Blunted Neural Responses to Reward in Major Depression.
Major depressive disorder (MDD) is a pernicious disorder characterized by deficits in reward processing. A better understanding of these deficits may help to elucidate the underlying pathophysiology and guide treatment development. This study assessed reward positivity and feedback negativity event-related potentials and their difference scores elicited in response to monetary gains and losses among 100 young adults (52 with MDD). Multilevel modeling was used to assess individual- and trial-level change in neural responses over time. Trial-level analyses indicated that a diagnosis of MDD and depressive symptom severity significantly moderated the trajectory of reward positivity, with individuals with higher symptoms of depression demonstrating less sensitivity to rewards over time. These results provide further support for reward dysfunction in MDD and highlight important individual differences in the trajectory of neural responses to reward. Future studies are warranted to investigate reward sensitivity over time to elucidate important individual- and trial-level differences in reward processing.
CognitiveConstruct
RewardProcessing
31,517,197
10.5334/joc.26
2,018
Journal of cognition
J Cogn
The Risks of Downplaying Top-Down Control.
Is top-down control necessarily scarce, slow, and hence unimportant in visual selection? Here we outline the risks of downplaying top-down control. Contrary to Theeuwes' review, we suggest that not all sources of attention map onto a unitary attentional priority map. Goals and search habits may influence where and how people deploy attention, respectively. Because goals have modulatory effects on sensory processing, their impact on attention is broad and not always deliberate. In addition, when multiple sources influence attention, top-down control often dominates over less deliberate forms of attention. We agree with Theeuwes that selection history can drive attention independent of explicit goals. Nonetheless, top-down control remains a cornerstone of visual selection.
CognitiveConstruct
RewardProcessing
29,749,715
10.1002/brb3.994
2,018
Brain and behavior
Brain Behav
Altered resting-state hippocampal and caudate functional networks in patients with obstructive sleep apnea.
Brain structural injury and metabolic deficits in the hippocampus and caudate nuclei may contribute to cognitive and emotional deficits found in obstructive sleep apnea (OSA) patients. If such contributions exist, resting-state interactions of these subcortical sites with cortical areas mediating affective symptoms and cognition should be disturbed. Our aim was to examine resting-state functional connectivity (FC) of the hippocampus and caudate to other brain areas in OSA relative to control subjects, and to relate these changes to mood and neuropsychological scores. We acquired resting-state functional magnetic resonance imaging (fMRI) data from 70 OSA and 89 healthy controls using a 3.0-Tesla magnetic resonance imaging scanner, and assessed psychological and behavioral functions, as well as sleep issues. After standard fMRI data preprocessing, FC maps were generated for bilateral hippocampi and caudate nuclei, and compared between groups (ANCOVA; covariates, age and gender). Obstructive sleep apnea subjects showed significantly higher levels of anxiety and depressive symptoms over healthy controls. In OSA subjects, the hippocampus showed disrupted FC with the thalamus, para-hippocampal gyrus, medial and superior temporal gyrus, insula, and posterior cingulate cortex. Left and right caudate nuclei showed impaired FC with the bilateral inferior frontal gyrus and right angular gyrus. In addition, altered limbic-striatal-cortical FC in OSA showed relationships with behavioral and neuropsychological variables. The compromised hippocampal-cortical FC in OSA may underlie depression and anxious mood levels in OSA, while impaired caudate-cortical FC may indicate deficits in reward processing and cognition. These findings provide insights into the neural mechanisms underlying the comorbidity of mood and cognitive deficits in OSA.
CognitiveConstruct
RewardProcessing
29,740,277
10.3389/fnins.2018.00271
2,018
Frontiers in neuroscience
Front Neurosci
Hedonic Eating and the "Delicious Circle": From Lipid-Derived Mediators to Brain Dopamine and Back.
Palatable food can be seductive and hedonic eating can become irresistible beyond hunger and negative consequences. This is witnessed by the subtle equilibrium between eating to provide energy intake for homeostatic functions, and reward-induced overeating. In recent years, considerable efforts have been devoted to study neural circuits, and to identify potential factors responsible for the derangement of homeostatic eating toward hedonic eating and addiction-like feeding behavior. Here, we examined recent literature on "old" and "new" players accountable for reward-induced overeating and possible liability to eating addiction. Thus, the role of midbrain dopamine is positioned at the intersection between selected hormonal signals involved in food reward information processing (namely, leptin, ghrelin, and insulin), and lipid-derived neural mediators such as endocannabinoids. The impact of high fat palatable food and dietary lipids on endocannabinoid formation is reviewed in its pathogenetic potential for the derangement of feeding homeostasis. Next, endocannabinoid signaling that regulates synaptic plasticity is discussed as a key mechanism acting both at hypothalamic and mesolimbic circuits, and affecting both dopamine function and interplay between leptin and ghrelin signaling. Outside the canonical hypothalamic feeding circuits involved in energy homeostasis and the notion of "feeding center," we focused on lateral hypothalamus as neural substrate able to confront food-associated homeostatic information with food salience, motivation to eat, reward-seeking, and development of compulsive eating. Thus, the lateral hypothalamus-ventral tegmental area-nucleus accumbens neural circuitry is reexamined in order to interrogate the functional interplay between ghrelin, dopamine, orexin, and endocannabinoid signaling. We suggested a pivotal role for endocannabinoids in food reward processing within the lateral hypothalamus, and for orexin neurons to integrate endocrine signals with food reinforcement and hedonic eating. In addition, the role played by different stressors in the reinstatement of preference for palatable food and food-seeking behavior is also considered in the light of endocannabinoid production, activation of orexin receptors and disinhibition of dopamine neurons. Finally, type-1 cannabinoid receptor-dependent inhibition of GABA-ergic release and relapse to reward-associated stimuli is linked to ghrelin and orexin signaling in the lateral hypothalamus-ventral tegmental area-nucleus accumbens network to highlight its pathological potential for food addiction-like behavior.
CognitiveConstruct
RewardProcessing
29,729,394
10.1016/j.neuroimage.2018.04.072
2,018
NeuroImage
Neuroimage
Neural correlates of gender differences in distractibility by sexual stimuli.
Attentional interference control is a prominent feature of human cognition. To what extent sexual stimuli attract attention and interfere with cognitive tasks has still little been studied. Our study aimed to identify associations between attentional interference, sexual arousal, trait sexual motivation, and neural activity to sexual distractors while accounting for gender differences. Therefore, the present study examined the neural correlates of attentional interference by arousing sexual distractors using functional magnetic resonance imaging (fMRI). Fifty women and 47 men underwent fMRI while indicating the orientation of two lines (equal or unequal) next to an explicit sexual (as compared to a neutral) picture. Results confirmed prolonged response times when a sexual image was shown. There was neither a difference between genders nor an effect of sexual arousal ratings or trait sexual motivation on distractibility. Neural activity specific to sexual images was found in brain regions implicated in motivation and reward processing. Men as compared to women showed stronger responses in the nucleus caudatus, the anterior cingulate cortex, and the nucleus accumbens. Trait sexual motivation was selectively correlated with nucleus caudatus activity. Taken together, findings support the notion that even when not in the focus, sexual images activate the brains' reward circuitry. Men's higher sensitivity to the rewarding value of sexual cues may be critical for their higher risk of addictive/compulsive sexual behaviors.
CognitiveConstruct
RewardProcessing
29,727,768
10.1016/j.bandc.2018.04.003
2,018
Brain and cognition
Brain Cogn
The neural correlates of attachment security in typically developing children.
This study investigated neural correlates of children's attachment security using functional magnetic resonance imaging. Fifty-one boys' attachment styles (age mean = 9.5 years, SD = 0.61) were assessed with the Separation Anxiety Test (SAT). We created an fMRI version of the SAT to activate children's attachment system in fMRI environment and contrasted two conditions in which children were instructed to infer the specific feeling of the boy in the picture or to identify objects or physical activities. In the final fMRI analysis (N = 21), attachment security could be detected at the neural level corresponding to the behavioural differences in the attachment interview. Securely attached children showed greater activation in the frontal, limbic and basal ganglia area which included the dorsolateral prefrontal cortex, amygdala, cingulate cortex and striatum, compared to other children who had lower quality of attachment. These regions have a key role in socio-emotional information processing and also represent a brain network related to approach and avoidance motivation in humans. Especially the striatum, strongly linked to reward processing underpinning social approach and avoidance motivation, showed the largest effects in these differences and also positively correlated with emotional openness scores in SAT. This suggests that the quality of attachment configures the approach and avoidance motivational system in our brain mediated by the striatum.
CognitiveConstruct
RewardProcessing
29,714,526
10.1080/00952990.2018.1461878
2,018
The American journal of drug and alcohol abuse
Am J Drug Alcohol Abuse
Brain intrinsic network connectivity in individuals with frequent tanning behavior.
Emergent studies suggest a bidirectional relationship between brain functioning and the skin. This neurocutaneous connection may be responsible for the reward response to tanning and, thus, may contribute to excessive tanning behavior. To date, however, this association has not yet been examined. To explore whether intrinsic brain functional connectivity within the default mode network (DMN) is related to indoor tanning behavior. Resting state functional connectivity (rsFC) was obtained in twenty adults (16 females) with a history of indoor tanning. Using a seed-based [(posterior cingulate cortex (PCC)] approach, the relationship between tanning severity and FC strength was assessed. Tanning severity was measured with symptom count from the Structured Clinical Interview for Tanning Abuse and Dependence (SITAD) and tanning intensity (lifetime indoor tanning episodes/years tanning). rsFC strength between the PCC and other DMN regions (left globus pallidus, left medial frontal gyrus, left superior frontal gyrus) is positively correlated with tanning symptom count. rsFC strength between the PCC and salience network regions (right anterior cingulate cortex, left inferior parietal lobe, left inferior temporal gyrus) is correlated with tanning intensity. Greater connectivity between tanning severity and DMN and salience network connectivity suggests that heightened self-awareness of salient stimuli may be a mechanism that underlies frequent tanning behavior. These findings add to the growing evidence of brain-skin connection and reflect dysregulation in the reward processing networks in those with frequent tanning.
CognitiveConstruct
RewardProcessing
29,707,167
10.1080/20008198.2018.1446616
2,018
European journal of psychotraumatology
Eur J Psychotraumatol
Anhedonia and emotional numbing in treatment-seeking veterans: behavioural and electrophysiological responses to reward.
: Anhedonia is a common symptom following exposure to traumatic stress and a feature of the PTSD diagnosis. In depression research, anhedonia has been linked to deficits in reward functioning, reflected in behavioural and neural responses. Such deficits following exposure to trauma, however, are not well understood. : The current study aims to estimate the associations between anhedonia, PTSD symptom-clusters and behavioural and electrophysiological responses to reward. : Participants ( = 61) were recruited among Danish treatment-seeking veterans at the Department of Military Psychology in the Danish Defence. Before entering treatment, participants were screened with symptom measurement instruments and participated in a joint behavioural-electrophysiological experiment. The experimental paradigm consisted of a signal-detection task aimed at assessing reward-driven learning. Simultaneous electrophysiological-recordings were analysed to evaluate neural responses upon receiving reward, as indicated by the Feedback-Related Negativity (FRN) component. : Anhedonia as conceptualized in depression correlated with behavioural learning ( = -0.28, = .032). Neither anhedonia nor behavioural learning correlated with FRN. However, the anhedonia symptom cluster of PTSD did correlate with FRN ( = 0.29, = .023). Extending upon this in an exploratory analysis, the specific PTSD-symptom emotional numbing was found to correlate moderately with FRN ( = 0.38, = .003). : The present data suggest that anhedonia in trauma-exposed individuals is related to the anticipatory aspect of reward, whereas the neural consummatory reward response seems unlinked. Interestingly, emotional numbing in the same population is related to the consummatory phase of reward, correlating with the FRN response. This suggests that anhedonia and emotional numbing in response to trauma might pertain to different phases of reward processing.
CognitiveConstruct
RewardProcessing
29,706,512
10.1016/j.cub.2018.03.038
2,018
Current biology : CB
Curr Biol
Decodability of Reward Learning Signals Predicts Mood Fluctuations.
Our mood often fluctuates without warning. Recent accounts propose that these fluctuations might be preceded by changes in how we process reward. According to this view, the degree to which reward improves our mood reflects not only characteristics of the reward itself (e.g., its magnitude) but also how receptive to reward we happen to be. Differences in receptivity to reward have been suggested to play an important role in the emergence of mood episodes in psychiatric disorders [1-16]. However, despite substantial theory, the relationship between reward processing and daily fluctuations of mood has yet to be tested directly. In particular, it is unclear whether the extent to which people respond to reward changes from day to day and whether such changes are followed by corresponding shifts in mood. Here, we use a novel mobile-phone platform with dense data sampling and wearable heart-rate and electroencephalographic sensors to examine mood and reward processing over an extended period of one week. Subjects regularly performed a trial-and-error choice task in which different choices were probabilistically rewarded. Subjects' choices revealed two complementary learning processes, one fast and one slow. Reward prediction errors [17, 18] indicative of these two processes were decodable from subjects' physiological responses. Strikingly, more accurate decodability of prediction-error signals reflective of the fast process predicted improvement in subjects' mood several hours later, whereas more accurate decodability of the slow process' signals predicted better mood a whole day later. We conclude that real-life mood fluctuations follow changes in responsivity to reward at multiple timescales.
CognitiveConstruct
RewardProcessing
29,704,424
10.1111/jnc.14455
2,018
Journal of neurochemistry
J Neurochem
The role of corticostriatal-hypothalamic neural circuits in feeding behaviour: implications for obesity.
Emerging evidence from human imaging studies suggests that obese individuals have altered connectivity between the hypothalamus, the key brain region controlling energy homeostasis, and cortical regions involved in decision-making and reward processing. Historically, animal studies have demonstrated that the lateral hypothalamus is the key hypothalamic region involved in feeding and reward. The lateral hypothalamus is a heterogeneous structure comprised of several distinct types of neurons which are scattered throughout. In addition, the lateral hypothalamus receives inputs from a number of cortical brain regions suggesting that it is uniquely positioned to be a key integrator of cortical information and metabolic feedback. In this review, we summarize how human brain imaging can inform detailed animal studies to investigate neural pathways connecting cortical regions and the hypothalamus. Here, we discuss key cortical brain regions that are reciprocally connected to the lateral hypothalamus and are implicated in decision-making processes surrounding food.
CognitiveConstruct
RewardProcessing
29,700,724
10.3758/s13415-018-0599-z
2,018
Cognitive, affective & behavioral neuroscience
Cogn Affect Behav Neurosci
Facing temptation: The neural correlates of gambling availability during sports picture exposure.
Nowadays, sports betting has become increasingly available and easy to engage in. Here we examined the neural responses to stimuli that represent sporting events available for betting as compared to sporting events without a gambling opportunity. We used a cue exposure task in which football (soccer) fans (N = 42) viewed cues depicting scheduled football games that would occur shortly after the scanning session. In the "betting" condition, participants were instructed to choose, at the end of each block, the game (and the team) they wanted to bet on. In the "watching" condition, participants chose the game they would prefer to watch. After the scanning session, participants completed posttask rating questionnaires assessing, for each cue, their level of confidence about the team they believed would win and how much they would enjoy watching the game. We found that stimuli representing sport events available for betting elicited higher fronto-striatal activation, as well as higher insular cortex activity and functional connectivity, than sport events without a gambling opportunity. Moreover, games rated with more confidence towards the winning team resulted in greater brain activations within regions involved in affective decision-making (ventromedial prefrontal cortex), cognitive inhibitory control (medial and superior frontal gyri) and reward processing (ventral and dorsal striatum). Altogether, these novel findings offer a sensible simulation of how the high availability of sports betting in today's environment impacts on the reward and cognitive control systems. Future studies are needed to extend the present findings to a sample of football fans that includes a samilar proportion of female and male participants.
CognitiveConstruct
RewardProcessing
29,691,918
10.1002/mpr.1615
2,018
International journal of methods in psychiatric research
Int J Methods Psychiatr Res
The relationships among aberrant salience, reward motivation, and reward sensitivity.
Change in reward processing and motivation may mediate the relationship between dopaminergic dysregulation and positive symptoms of schizophrenia. We sought to investigate the measurement of aberrant salience and its relationship with behavioural measures of reward and motivation. Participants (n = 82) completed measures of aberrant salience (Aberrant Salience Inventory and Salience Attribution Task), motivation (Effort Expenditure for Rewards Task), and reinforcer sensitivity (Stimulus Chase Task). Hypotheses were tested using correlation and generalised linear modelling. Results indicated no relationship between aberrant salience measures. The Aberrant Salience Inventory was positively related to effort expenditure for lower less likely rewards and predicted the use of probability alone in decision-making. The only significant relationship between reward and motivation was a positive relationship between gain sensitivity and motivated behaviour for higher more likely rewards. Although some support for a relationship between measures of reward motivation and aberrant salience were found, there was no evidence that the aberrant salience measures had concurrent validity. Our results suggest caution is warranted when interpreting measures of aberrant salience.
CognitiveConstruct
RewardProcessing
29,687,649
10.1002/oby.22165
2,018
Obesity (Silver Spring, Md.)
Obesity (Silver Spring)
Neural Food Reward Processing in Successful and Unsuccessful Weight Maintenance.
Weight loss maintenance is one of the biggest challenges in behavioral weight loss programs. The present study aimed to examine metabolic influences on the mesolimbic reward system in people with successful and unsuccessful long-term weight loss maintenance. Thirty-three women with obesity at least 6 months after the completion of a diet were recruited: seventeen women were able to maintain their weight loss, whereas sixteen showed weight regain. Using functional magnetic resonance imaging in combination with the assessment of appetite-regulating hormones, neural reward processing during hunger and satiety was investigated. An incentive delay task was employed to investigate the expectation and receipt of both food-related and monetary reward. Only participants with successful weight loss maintenance showed a satiety-induced attenuation of brain activation during the receipt of a food-related reward. Furthermore, in successful weight loss maintenance, the attenuation of active ghrelin levels was related to brain activation in response to food-related reward anticipation during satiety. The findings suggest that an attenuated influence of satiety signaling on the neural processing of food-related reward contributes to unsuccessful weight loss maintenance. Thus, intact satiety signaling to the mesolimbic reward system may serve as a promising target for tackling weight cycling.
CognitiveConstruct
RewardProcessing
29,687,627
10.1111/cns.12854
2,018
CNS neuroscience & therapeutics
CNS Neurosci Ther
Anhedonia in depression and schizophrenia: A transdiagnostic challenge.
Anhedonia, as a dysregulation of the reward circuit, is present in both Major Depressive Disorder (MDD) and schizophrenia (SZ). To elucidate the clinical and neurobiological differences between schizophrenia (SZ) and depression (MDD) in regard to anhedonia, while reconciling the challenges and benefits of assessing anhedonia as a transdiagnostic feature under the Research Domain Criteria (RDoC) framework. In this review, we summarize data from publications examining anhedonia or its underlying reward deficits in SZ and MDD. A literature search was conducted in OVID Medline, PsycINFO and EMBASE databases between 2000 and 2017. While certain subgroups share commonalities, there are also important differences. SZ may be characterized by a disorganization, rather than a deficiency, in reward processing and cognitive function, including inappropriate energy expenditure and focus on irrelevant cues. In contrast, MDD has been characterized by deficits in anticipatory pleasure, development of reward associations, and integration of information from past experience. Understanding the roles of neurotransmitters and aberrant brain circuitry is necessary to appreciate differences in reward function in SZ and MDD. Anhedonia as a clinical presentation of reward circuit dysregulation is an important and relatively undertreated symptom of both SZ and MDD. In order to improve patient outcomes and quality of life, it is important to consider how anhedonia fits into both diagnoses.
CognitiveConstruct
RewardProcessing
29,684,536
10.1016/j.pnpbp.2018.04.009
2,019
Progress in neuro-psychopharmacology & biological psychiatry
Prog Neuropsychopharmacol Biol Psychiatry
Gender-related functional connectivity and craving during gaming and immediate abstinence during a mandatory break: Implications for development and progression of internet gaming disorder.
Although males more frequently develop Internet gaming disorder (IGD) as compared with females, few studies have examined gender-related neurocognitive differences in IGD. TASK AND DESIGN: fMRI and subjective data were collected from 119 subjects (IGD, male 29, female 25; recreational game use (RGU), male 34, female 31) when they were actively playing games and during a forced mandatory break. Analyses investigating effects of group (IGD, RGU) and gender (male, female) on the functional connectivity (FC) of executive control and reward systems linked to the dorsolateral prefrontal cortex (DLPFC) and striatum, respectively, were performed. Correlations between FC and subjective craving measures were also calculated. Gaming-group-by-gender interactions were observed. During gaming in males but not in females, the FC between the DLPFC and superior frontal gyrus was relatively decreased, and that between the striatum and thalamus was relatively increased. During the mandatory break, changes in the FC between DLPFC and superior frontal gyrus and the FC between the striatum and thalamus varied by gender with greater RGU-IGD differences observed in females. Significant correlations between FC and self-reported craving were observed. During both gaming and a forced mandatory break, brain regions implicated in executive control and reward processing showed changes in FC that varied by gender. Brain regions implicated in executive control showed differential FC in males during gaming, and FC during the forced mandatory break appeared relevant to both genders, and perhaps particularly for females. The findings suggest possible neural mechanisms for why males appear more likely to develop IGD, and why it may be particularly difficult for individuals with IGD to cease gaming.
CognitiveConstruct
RewardProcessing
29,684,476
10.1016/j.bbr.2018.04.018
2,018
Behavioural brain research
Behav Brain Res
The dorsal diencephalic conduction system in reward processing: Spotlight on the anatomy and functions of the habenular complex.
The dorsal diencephalic conduction system (DDC) is a highly conserved pathway in vertebrates that provides a route for the neural information to flow from forebrain to midbrain structures. It contains the bilaterally paired habenular nuclei along with two fiber tracts, the stria medullaris and the fasciculus retroflexus. The habenula is the principal player in mediating the dialogue between forebrain and midbrain regions, and functional abnormalities in this structure have often been attributed to pathologies like mood disorders and substance use disorder. Following Matsumoto and Hikosaka seminal work on the lateral habenula as a source of negative reward signals, the last decade has witnessed a great surge of interest in the role of the DDC in reward-related processes. However, despite significant progress in research, much work remains to unfold the behavioral functions of this intriguing, yet complex, pathway. This review describes the current state of knowledge on the DDC with respect to its anatomy, connectivity, and functions in reward and aversion processes.
CognitiveConstruct
RewardProcessing
29,681,866
10.3389/fpsyt.2018.00024
2,018
Frontiers in psychiatry
Front Psychiatry
Study Protocol: Using Deep-Brain Stimulation, Multimodal Neuroimaging and Neuroethics to Understand and Treat Severe Enduring Anorexia Nervosa.
Research suggests that altered eating and the pursuit of thinness in anorexia nervosa (AN) are, in part, a consequence of aberrant reward circuitry. The neural circuits involved in reward processing and compulsivity overlap significantly, and this has been suggested as a transdiagnostic factor underpinning obsessive compulsive disorder, addictions and eating disorders. The nucleus accumbens (NAcc) is central to both reward processing and compulsivity. In previous studies, deep-brain stimulation (DBS) to the NAcc has been shown to result in neural and symptomatic improvement in both obsessive compulsive disorder and addictions. Moreover, in rats, DBS to the NAcc medial shell increases food intake. We hypothesise that this treatment may be of benefit in severe and enduring anorexia nervosa (SE-AN), but first, feasibility and ethical standards need to be established. The aims of this study are as follows: (1) to provide feasibility and preliminary efficacy data on DBS to the NAcc as a treatment for SE-AN; (2) to assess any subsequent neural changes and (3) to develop a neuroethical gold standard to guide applications of this treatment. This is a longitudinal study of six individuals with SE-AN of >7 years. It includes an integrated neuroethical sub-study. DBS will be applied to the NAcc and we will track the mechanisms underpinning AN using magnetoelectroencephalography, neuropsychological and behavioural measures. Serial measures will be taken on each intensively studied patient, pre- and post-DBS system insertion. This will allow elucidation of the processes involved in symptomatic change over a 15-month period, which includes a double-blind crossover phase of stimulator on/off. Novel, empirical treatments for SE-AN are urgently required due to high morbidity and mortality costs. If feasible and effective, DBS to the NAcc could be game-changing in the management of this condition. A neuroethical gold standard is crucial to optimally underpin such treatment development. The study is ongoing and registered with www.ClinicalTrials.gov, https://clinicaltrials.gov/ct2/show/NCT01924598, 22 July, 2013. It has full ethical and HRA approval (Project ID 128658).
CognitiveConstruct
RewardProcessing
29,669,599
10.1186/s13722-018-0115-3
2,018
Addiction science & clinical practice
Addict Sci Clin Pract
Mindfulness-based treatment of addiction: current state of the field and envisioning the next wave of research.
Contemporary advances in addiction neuroscience have paralleled increasing interest in the ancient mental training practice of mindfulness meditation as a potential therapy for addiction. In the past decade, mindfulness-based interventions (MBIs) have been studied as a treatment for an array addictive behaviors, including drinking, smoking, opioid misuse, and use of illicit substances like cocaine and heroin. This article reviews current research evaluating MBIs as a treatment for addiction, with a focus on findings pertaining to clinical outcomes and biobehavioral mechanisms. Studies indicate that MBIs reduce substance misuse and craving by modulating cognitive, affective, and psychophysiological processes integral to self-regulation and reward processing. This integrative review provides the basis for manifold recommendations regarding the next wave of research needed to firmly establish the efficacy of MBIs and elucidate the mechanistic pathways by which these therapies ameliorate addiction. Issues pertaining to MBI treatment optimization and sequencing, dissemination and implementation, dose-response relationships, and research rigor and reproducibility are discussed.
CognitiveConstruct
RewardProcessing
29,662,095
10.1038/s41467-018-03848-y
2,018
Nature communications
Nat Commun
μ-opioid receptor system mediates reward processing in humans.
The endogenous μ-opioid receptor (MOR) system regulates motivational and hedonic processing. We tested directly whether individual differences in MOR are associated with neural reward responses to food pictures in humans. We scanned 33 non-obese individuals with positron emission tomography (PET) using the MOR-specific radioligand [C]carfentanil. During a functional magnetic resonance imaging (fMRI) scan, the subjects viewed pictures of appetizing versus bland foods to elicit reward responses. MOR availability was measured in key components of the reward and emotion circuits and used to predict BOLD-fMRI responses to foods. Viewing palatable versus bland foods activates regions involved in homeostatic and reward processing, such as amygdala, ventral striatum, and hypothalamus. MOR availability in the reward and emotion circuit is negatively associated with the fMRI reward responses. Variation in MOR availability may explain why some people feel an urge to eat when encountering food cues, increasing risk for weight gain and obesity.
CognitiveConstruct
RewardProcessing
29,626,342
10.1111/jopy.12390
2,019
Journal of personality
J Pers
A neuroscientific perspective on basic psychological needs.
Self-determination theory's (SDT) most basic propositions are, first, that all people possess an inherent set of psychological needs and, second, that autonomy, competence, and relatedness are the three critical psychological satisfactions needed to maintain and promote personal growth and well-being. In this article, we identify the neural basis of the psychological needs and, in doing so, seek to advance the integration of SDT and neuroscience. We examine the neural underpinnings of SDT-based motivational states and traits for autonomy, competence, and relatedness. To study motivational states, participants are exposed to situational conditions known to affect their psychological needs, and neuroscience methods (e.g., fMRI) are used to examine changes in their brain activity. To study motivational traits, participants complete self-report trait measures that are then correlated with their brain activity observed during need-satisfying activities. For both motivational states and traits and across all three needs, intrinsic satisfaction is associated with striatum-based reward processing, anterior insula-based subjective feelings, and the integration of these subjective feelings with reward-based processing. Psychological need satisfaction is associated with striatum activity, anterior insula activity, and the functional coactivation between these two brain areas. Given these findings, it is now clear that several opportunities exist to integrate SDT motivational constructs with neuroscientific study, so we suggest eight new questions for future research.
CognitiveConstruct
RewardProcessing
29,616,472
10.3758/s13415-018-0586-4
2,018
Cognitive, affective & behavioral neuroscience
Cogn Affect Behav Neurosci
Risk seeking for losses modulates the functional connectivity of the default mode and left frontoparietal networks in young males.
Value-based decision making (VBDM) is a principle that states that humans and other species adapt their behavior according to the dynamic subjective values of the chosen or unchosen options. The neural bases of this process have been extensively investigated using task-based fMRI and lesion studies. However, the growing field of resting-state functional connectivity (RSFC) may shed light on the organization and function of brain connections across different decision-making domains. With this aim, we used independent component analysis to study the brain network dynamics in a large cohort of young males (N = 145) and the relationship of these dynamics with VBDM. Participants completed a battery of behavioral tests that evaluated delay aversion, risk seeking for losses, risk aversion for gains, and loss aversion, followed by an RSFC scan session. We identified a set of large-scale brain networks and conducted our analysis only on the default mode network (DMN) and networks comprising cognitive control, appetitive-driven, and reward-processing regions. Higher risk seeking for losses was associated with increased connectivity between medial temporal regions, frontal regions, and the DMN. Higher risk seeking for losses was also associated with increased coupling between the left frontoparietal network and occipital cortices. These associations illustrate the participation of brain regions involved in prospective thinking, affective decision making, and visual processing in participants who are greater risk-seekers, and they demonstrate the sensitivity of RSFC to detect brain connectivity differences associated with distinct VBDM parameters.
CognitiveConstruct
RewardProcessing
29,608,775
10.1093/schbul/sby037
2,019
Schizophrenia bulletin
Schizophr Bull
Structural and Functional Neuroimaging of Polygenic Risk for Schizophrenia: A Recall-by-Genotype-Based Approach.
Risk profile scores (RPS) derived from genome-wide association studies (GWAS) explain a considerable amount of susceptibility for schizophrenia (SCZ). However, little is known about how common genetic risk factors for SCZ influence the structure and function of the human brain, largely due to the constraints of imaging sample sizes. In the current study, we use a novel recall-by-genotype (RbG) methodological approach, where we sample young adults from a population cohort (Avon Longitudinal Study of Parents and Children: N genotyped = 8365) based on their SCZ-RPS. We compared 197 healthy individuals at extremes of low (N = 99) or high (N = 98) SCZ-RPS with behavioral tests, and structural and functional magnetic resonance imaging (fMRI). We first provide methodological details that will inform the design of future RbG studies for common SCZ genetic risk. We further provide an between group analysis of the RbG individuals (low vs high SCZ-RPS) who underwent structural neuroimaging data (T1-weighted scans) and fMRI data during a reversal learning task. While we found little evidence for morphometric differences between the low and high SCZ-RPS groups, we observed an impact of SCZ-RPS on blood oxygen level-dependent (BOLD) signal during reward processing in the ventral striatum (PFWE-VS-CORRECTED = .037), a previously investigated broader reward-related network (PFWE-ROIS-CORRECTED = .008), and across the whole brain (PFWE-WHOLE-BRAIN-CORRECTED = .013). We also describe the study strategy and discuss specific challenges of RbG for SCZ risk (such as SCZ-RPS related homoscedasticity). This study will help to elucidate the behavioral and imaging phenotypes that are associated with SCZ genetic risk.
CognitiveConstruct
RewardProcessing
29,605,579
10.1016/j.neuroimage.2018.03.067
2,018
NeuroImage
Neuroimage
Noninvasive stimulation of the ventromedial prefrontal cortex modulates emotional face processing.
The ventromedial prefrontal cortex (vmPFC) is associated with emotional states that can be characterized as positive affect. Moreover, a variety of psychiatric disorders that are associated with disturbed reactions toward reward- or safety-signaling stimuli reveal functional or structural anomalies within this area. Thus, neuromodulation of this region via transcranial direct current stimulation (tDCS) offers an attractive opportunity to noninvasively influence pleasant emotional and reward processing. Recent experiments revealed hemodynamic and electrophysiological evidence for valence specific modulations of emotional scene processing after excitatory and inhibitory tDCS of the vmPFC. Here, we identified that tDCS modulation of vmPFC during emotional face processing results in effects convergent with scene processing, in that excitatory tDCS increased neural reactivity during happy compared to fearful face perception, whereas inhibitory stimulation led to a converse effect. In addition, behavioral data (affect identification of ambiguous expressive faces) revealed a bias toward preferential processing of happy compared to fearful faces after excitatory compared to after inhibitory stimulation. These results further support the vmPFC as an appropriate target for noninvasive neuromodulation of an appetitive processing network in patients suffering from disturbed cognition of reward- and safety-signaling stimuli. It should however be noted that electrophysiological pre-tDCS differences at earlier time intervals of emotional face and scene processing appeared amplified by tDCS, which remains to be investigated.
CognitiveConstruct
RewardProcessing
29,601,896
10.1016/j.pnpbp.2018.03.022
2,019
Progress in neuro-psychopharmacology & biological psychiatry
Prog Neuropsychopharmacol Biol Psychiatry
Differentiating between bipolar and unipolar depression in functional and structural MRI studies.
Distinguishing depression in bipolar disorder (BD) from unipolar depression (UD) solely based on clinical clues is difficult, which has led to the exploration of promising neural markers in neuroimaging measures for discriminating between BD depression and UD. In this article, we review structural and functional magnetic resonance imaging (MRI) studies that directly compare UD and BD depression based on neuroimaging modalities including functional MRI studies on regional brain activation or functional connectivity, structural MRI on gray or white matter morphology, and pattern classification analyses using a machine learning approach. Numerous studies have reported distinct functional and structural alterations in emotion- or reward-processing neural circuits between BD depression and UD. Different activation patterns in neural networks including the amygdala, anterior cingulate cortex (ACC), prefrontal cortex (PFC), and striatum during emotion-, reward-, or cognition-related tasks have been reported between BD and UD. A stronger functional connectivity pattern in BD was pronounced in default mode and in frontoparietal networks and brain regions including the PFC, ACC, parietal and temporal regions, and thalamus compared to UD. Gray matter volume differences in the ACC, hippocampus, amygdala, and dorsolateral prefrontal cortex (DLPFC) have been reported between BD and UD, along with a thinner DLPFC in BD compared to UD. BD showed reduced integrity in the anterior part of the corpus callosum and posterior cingulum compared to UD. Several studies performed pattern classification analysis using structural and functional MRI data to distinguish between UD and BD depression using a supervised machine learning approach, which yielded a moderate level of accuracy in classification.
CognitiveConstruct
RewardProcessing
29,600,513
10.1111/psyp.13081
2,018
Psychophysiology
Psychophysiology
Alcohol hangover impacts learning and reward processing within the medial-frontal cortex.
It is common knowledge that alcohol intoxication impairs motor coordination, judgment, and decision making. Indeed, an abundance of literature links intoxication to impaired cognitive control that leads to accidents and injury. A broadening body of research, however, suggests that the impact of alcohol may continue beyond the point of intoxication and into the period of alcohol hangover. Here, we examined differences in the amplitude of reward positivity-a component of the human ERP associated with learning-between control and hangover participants. During performance of a learnable gambling task, we found a reduction in the reward positivity during alcohol hangover. Additionally, participants experiencing alcohol hangover demonstrated reduced performance in the experimental task in comparison to their nonhangover counterparts. Our results suggest that the neural systems that underlie performance monitoring and reward-based learning are impaired during alcohol hangover.
CognitiveConstruct
RewardProcessing
29,594,872
10.1007/s11682-018-9856-6
2,019
Brain imaging and behavior
Brain Imaging Behav
Calcium/calmodulin-stimulated adenylyl cyclases 1 and 8 regulate reward-related brain activity and ethanol consumption.
Evidence suggests a predictive link between elevated basal activity within reward-related networks (e.g., cortico-basal ganglia-thalamic networks) and vulnerability for alcoholism. Both calcium channel function and cyclic adenosine monophosphate (cAMP)/protein kinase A-mediated signaling are critical modulators of reward neurocircuitry and reward-related behaviors. Calcium/calmodulin-stimulated adenylyl cyclases (AC) 1 and 8 are sensitive to activity-dependent increases in intracellular calcium and catalyze cAMP production. Therefore, we hypothesized AC1 and 8 regulate brain activity in reward regions of the cortico-basal ganglia-thalamic circuit and that this regulatory influence predicts voluntary ethanol drinking responses. This hypothesis was evaluated by manganese-enhanced magnetic resonance imaging and chronic, intermittent ethanol access procedures. Ethanol-naïve mice with genetic deletion of both AC1 and 8 (DKO mice) exhibited bilateral reductions in baseline activity within cortico-basal ganglia-thalamic regions associated with reward processing compared to wild-type controls (WT, C57BL/6 mice). Significant activity changes were not evident in regions either outside of the cortico-basal ganglia-thalamic network or within the network that are not associated with reward processing. Parallel studies demonstrated that reward network hypoactivity in DKO mice predicted a significant attenuation in consumption and preference levels to escalating ethanol concentrations (12, 20 and 30%) compared to WT mice, an effect that was maintained over extended access (14 sessions) to 20% ethanol. Summarizing, these data support a contribution of AC1 and 8 in cortico-basal ganglia-thalamic activity and the predictive value of this regulatory influence on ethanol drinking behavior, which merits the future evaluation of calcium-stimulated ACs in the neural processes that engender vulnerability to maladaptive alcohol drinking.
CognitiveConstruct
RewardProcessing
29,587,625
10.1186/s11689-018-9228-y
2,018
Journal of neurodevelopmental disorders
J Neurodev Disord
The effects of intranasal oxytocin on reward circuitry responses in children with autism spectrum disorder.
Intranasal oxytocin (OT) has been shown to improve social communication functioning of individuals with autism spectrum disorder (ASD) and, thus, has received considerable interest as a potential ASD therapeutic agent. Although preclinical research indicates that OT modulates the functional output of the mesocorticolimbic dopamine system that processes rewards, no clinical brain imaging study to date has examined the effects of OT on this system using a reward processing paradigm. To address this, we used an incentive delay task to examine the effects of a single dose of intranasal OT, versus placebo (PLC), on neural responses to social and nonsocial rewards in children with ASD. In this placebo-controlled double-blind study, 28 children and adolescents with ASD (age: M = 13.43 years, SD = 2.36) completed two fMRI scans, one after intranasal OT administration and one after PLC administration. During both scanning sessions, participants completed social and nonsocial incentive delay tasks. Task-based neural activation and connectivity were examined to assess the impact of OT relative to PLC on mesocorticolimbic brain responses to social and nonsocial reward anticipation and outcomes. Central analyses compared the OT and PLC conditions. During nonsocial reward anticipation, there was greater activation in the right nucleus accumbens (NAcc), left anterior cingulate cortex (ACC), bilateral orbital frontal cortex (OFC), left superior frontal cortex, and right frontal pole (FP) during the OT condition relative to PLC. Alternatively, during social reward anticipation and outcomes, there were no significant increases in brain activation during the OT condition relative to PLC. A Treatment Group × Reward Condition interaction revealed relatively greater activation in the right NAcc, right caudate nucleus, left ACC, and right OFC during nonsocial relative to social reward anticipation during the OT condition relative to PLC. Additionally, these analyses revealed greater activation during nonsocial reward outcomes during the OT condition relative to PLC in the right OFC and left FP. Finally, functional connectivity analyses generally revealed changes in frontostriatal connections during the OT condition relative to PLC in response to nonsocial, but not social, rewards. The effects of intranasal OT administration on mesocorticolimbic brain systems that process rewards in ASD were observable primarily during the processing of nonsocial incentive salience stimuli. These findings have implications for understanding the effects of OT on neural systems that process rewards, as well as for experimental trials of novel ASD treatments developed to ameliorate social communication impairments in ASD.
CognitiveConstruct
RewardProcessing
29,584,917
10.1093/ntr/nty059
2,019
Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco
Nicotine Tob Res
The Effects of Nicotine and Tobacco Use on Brain Reward Function: Interaction With Nicotine Dependence Severity.
This study investigated the effects of nicotine/tobacco on neural activation during performance of a monetary incentive delay task. Prior to each scan, nonsmokers received nicotine or placebo nasal spray, and smokers were smoking satiated or 24-hour withdrawn. During the scan, participants made timed responses to reward-related cues and received feedback. Parameter estimates from cue- and feedback-related activation in medial prefrontal regions and the nucleus accumbens were extracted and underwent within- and between-group analyses. Smokers' nicotine dependence severity was included as a continuous predictor variable for neural activation. Among smokers (n = 21), withdrawal decreased cue-related activation in the supplementary motor area and ventromedial prefrontal cortex, and the difference in activation (satiety > withdrawal) in these regions negatively correlated with nicotine dependence severity (Fagerström Test for Nicotine Dependence). Among nonsmokers (n = 22), nicotine increased the difference in nucleus accumbens activation between rewarded and nonrewarded feedback phases. Tobacco withdrawal and acute nicotine also had widespread effects on activation throughout the brain during the feedback phase. Acute nicotine in nonsmokers may have increased the salience of feedback information, but produced few effects on reward-related activation overall, perhaps reflecting nicotine's modest, indirect effects on reward processing. Conversely, tobacco withdrawal decreased activation compared with satiety, and this difference between conditions correlated with nicotine dependence severity. This suggests that as smokers become more dependent on nicotine, tobacco withdrawal has a more pronounced effect on reward processing. Relative to the acute effects of nicotine in nonsmokers, withdrawal from daily tobacco use had more significant effects on reward-related brain activation. This study suggests that the effects of tobacco withdrawal on reward-related brain function interact with subjects' level of nicotine dependence severity. These are potentially important sources of variability that could contribute to smoking cessation outcomes.
CognitiveConstruct
RewardProcessing
29,579,064
10.1371/journal.pone.0191059
2,018
PloS one
PLoS One
Neural processing of food and emotional stimuli in adolescent and adult anorexia nervosa patients.
A constant preoccupation with food and restrictive eating are main symptoms of anorexia nervosa (AN). Imaging studies revealed aberrant neural activation patterns in brain regions processing hedonic and reward reactions as well as-potentially aversive-emotions. An imbalance between so called "bottom-up" and "top-down" control areas is discussed. The present study is focusing on neural processing of disease-specific food stimuli and emotional stimuli and its developmental course in adolescent and adult AN patients and could offer new insight into differential mechanisms underlying shorter or more chronic disease. 33 adolescents aged 12-18 years (15 AN patients, 18 control participants) and 32 adult women (16 AN patients, 16 control participants) underwent functional magnetic resonance imaging (fMRI, 3T high-field scanner) while watching pictures of high and low-calorie food and affective stimuli. Afterwards, they rated subjective valence of each picture. FMRI data analysis was performed using a region of interest based approach. Pictures of high-calorie food items were rated more negatively by AN patients. Differences in activation between patients and controls were found in "bottom up" and "top down" control areas for food stimuli and in several emotion processing regions for affective stimuli which were more pronounced in adolescents than in adults. A differential pattern was seen for food stimuli compared to generally emotion eliciting stimuli. Adolescents with AN show reduced processing of affective stimuli and enhanced activation of regions involved in "bottom up" reward processing and "top down" control as well as the insula with regard to food stimuli with a focus on brain regions which underlie changes during adolescent development. In adults less clear and less specific activation differences were present, pointing towards a high impact that regions undergoing maturation might have on AN symptoms.
CognitiveConstruct
RewardProcessing
29,574,232
10.1016/j.ijpsycho.2018.03.014
2,018
International journal of psychophysiology : official journal of the International Organization of Psychophysiology
Int J Psychophysiol
Individual differences in self-reported reward-approach tendencies relate to resting-state and reward-task-based fMRI measures.
In this study, we investigated neural responses during resting-state and reward-task-based fMRI and how these related to individual differences in self-reported reward sensitivity. Resting-state fMRI data were collected from 191 college students, and 60 of these individuals further finished a reward-related fMRI task. Self-reported reward-approach tendencies were assessed using the behavioral activation scale. Behavioral activation scale scores were positively correlated with brain activations in the striatum bilaterally during reward processing. During rest, behavioral activation scale scores were positively correlated with functional connectivity between the left and right striatum and with functional connectivity between the right striatum and right middle frontal gyrus. Positive correlations were found between task-based striatal activations and the functional connectivity between the left and right striatum at rest. These results suggest a relationship between striatal task-based reward-related activations and resting connectivity strengths that relate to individual differences in reward-approach tendencies.
CognitiveConstruct
RewardProcessing
29,573,471
10.1002/gps.4877
2,018
International journal of geriatric psychiatry
Int J Geriatr Psychiatry
Reward learning impairment and avoidance and rumination responses at the end of Engage therapy of late-life depression.
This study examined the association between reward processing, as measured by performance on the probabilistic reversal learning (PRL) task and avoidance/rumination in depressed older adults treated with Engage, a psychotherapy that uses "reward exposure" to increase behavioral activation. Thirty older adults with major depression received 9 weeks of Engage treatment. At baseline and treatment end, the 24-item Hamilton Depression Rating Scale (HAM-D) was used to assess depression severity and the Behavioral Activation for Depression Scale (BADS) to assess behavioral activation and avoidance/rumination. Participants completed the PRL task at baseline and at treatment end. The PRL requires participants to learn stimulus-reward contingencies through trial and error, and switch strategies when the contingencies unexpectedly change. At the end of Engage treatment, the severity of depression was lower (HAM-D: t(19) = -7.67, P < .001) and behavioral activation was higher (BADS: t(19) = 2.23, P = .02) compared to baseline. Response time following all switches (r(19) = -0.63, P = .003) and error switches (r(19) = -0.57, P = .01) at baseline was negatively associated with the BADS avoidance/rumination subscale score at the end of Engage treatment. Impaired reward learning, evidenced by slower response following all switches and error switches, contributes to avoidant, ruminative behavior at the end of Engage therapy even when depression improves. Understanding reward processing abnormalities of avoidance and rumination may improve the timing and targeting of interventions for these symptoms, whose persistence compromises quality of life and increases the risk of depression relapse.
CognitiveConstruct
RewardProcessing
29,573,379
10.1515/revneuro-2017-0091
2,018
Reviews in the neurosciences
Rev Neurosci
Dopamine dysregulation hypothesis: the common basis for motivational anhedonia in major depressive disorder and schizophrenia?
Abnormalities in reward processing are crucial symptoms of major depressive disorder (MDD) and schizophrenia (SCH). Recent neuroscientific findings regarding MDD have led to conclusions about two different symptoms related to reward processing: motivational and consummatory anhedonia, corresponding, respectively, to impaired motivation to obtain rewards ('wanting'), and diminished satisfaction from consuming them ('liking'). One can ask: which of these is common for MDD and SCH. In our review of the latest neuroscientific studies, we show that MDD and SCH do not share consummatory anhedonia, as SCH patients usually have unaltered liking. Therefore, we investigated whether motivational anhedonia is the common symptom across MDD and SCH. With regard to the similarities and differences between the neural mechanisms of MDD and SCH, here we expand the current knowledge of motivation deficits and present the common underlying mechanism of motivational anhedonia - the dopamine dysregulation hypothesis - stating that any prolonged dysregulation in tonic dopamine signaling that exceeds the given equilibrium can lead to striatal dysfunction and motivational anhedonia. The implications for further research and treatment of MDD and SCH are also discussed.
CognitiveConstruct
RewardProcessing
29,567,510
10.1016/j.jpsychires.2018.02.002
2,018
Journal of psychiatric research
J Psychiatr Res
The effects of early life stress on reward processing.
Early life stress (ELS), in the form of childhood maltreatment, abuse, or neglect, increases the risk for psychiatric sequelae later in life. The neurobiology of response to early stress and of reward processing overlap substantially, leading to the prediction that reward processing may be a primary mediator of the effects of early life stress. We describe a growing body of literature investigating the effects of early life stressors on reward processing in animals and humans. Despite variation in the reviewed studies, an emerging pattern of results indicates that ELS results in deficits of ventral striatum-related functions of reward responsiveness and approach motivation, especially when the stressor is experienced in early in development. For stressors experienced later in the juvenile period and adolescence, the animal literature suggests an opposite effect, in which ELS results in increased hedonic drive. Future research in this area will help elucidate the transdiagnostic impact of early life stress, and therefore potentially identify and intervene with at-risk youth, prior to the emergence of clinical psychopathology.
CognitiveConstruct
RewardProcessing
29,558,817
10.1176/appi.ajp.2018.17070777
2,018
The American journal of psychiatry
Am J Psychiatry
Developmental Trajectories of the Orbitofrontal Cortex and Anhedonia in Middle Childhood and Risk for Substance Use in Adolescence in a Longitudinal Sample of Depressed and Healthy Preschoolers.
Deficits in reward processing are established in mood and substance use disorders and are known risk factors for these disorders. Volume reductions of the orbitofrontal cortex and the striatum, regions that subserve neural response to reward, have been shown to be related to anhedonia in depressive and substance use disorders. The authors sought to investigate how structural maturation of these regions in childhood varies with level of anhedonia and predicts later substance use. The study employed data from a sample of depressed and healthy preschoolers studied longitudinally that included three waves of neuroimaging from school age to adolescence. Three years after scan 3, at ages 13-18, participants underwent a comprehensive behavioral and substance use assessment. Multilevel modeling was used to investigate the relationship between anhedonia and the growth trajectories of the striatum and orbitofrontal cortex. Zero-inflated Poisson regression models were then used to determine whether the intercepts and slopes of these trajectories predicted later alcohol and marijuana use frequency in adolescence. The anhedonia-by-age interaction was significant in the multilevel modeling of orbitofrontal cortical but not striatal volume. Higher anhedonia ratings were significantly associated with steeper decline in orbitofrontal cortical volume with age. Orbitofrontal cortical volume and thickness at age 12 and trajectory over time significantly and negatively predicted subsequent alcohol and marijuana use frequency but not depression during adolescence. The findings suggest that the development of the orbitofrontal cortex during childhood is strongly linked to experiences of anhedonia and that these growth trajectories predict substance use during a developmentally critical period.
CognitiveConstruct
RewardProcessing
29,556,859
10.1007/s10802-018-0421-y
2,018
Journal of abnormal child psychology
J Abnorm Child Psychol
Children's Reward and Punishment Sensitivity Moderates the Association of Negative and Positive Parenting Behaviors in Child ADHD Symptoms.
Atypical reward processing, including abnormal reward responsivity and sensitivity to punishment, has long been implicated in the etiology of ADHD. However, little is known about how these facets of behavior interact with positive (e.g., warmth, praise) and negative (e.g., hostility, harsh discipline) parenting behavior in the early expression of ADHD symptoms in young children. Understanding the interplay between children's reward processing and parenting may be crucial for identifying specific treatment targets in psychosocial interventions for ADHD, especially given that not all children benefit from contingency-based treatments (e.g., parent management training). The study consisted of a sample of kindergarten children (N = 201, 55% male) and their parents, who completed questionnaires about their parenting practices, their child's behaviors and participated in an observed parent-child play task in the laboratory. Children's reward responsivity and sensitivity to punishment were positively associated with child ADHD symptoms. However, children with high reward responsivity had more symptoms of ADHD but only under conditions of low negative parenting (self-reported and observed) and high self-reported positive parenting, compared to children with low reward responsivity. Children with high sensitivity to punishment had more ADHD symptoms relative to children with low sensitivity to punishment, but only under conditions in which observed praise was infrequent. Results provide evidence that individual differences in sensitivity to reward/punishment may be an important of marker of risk for ADHD, but also highlights how children's responses to positive and negative parenting behavior may vary by children's sensitivities. Clinical and treatment implications are discussed.
CognitiveConstruct
RewardProcessing
29,535,396
10.1038/s41598-018-22605-1
2,018
Scientific reports
Sci Rep
Development and validation of the Canine Reward Responsiveness Scale -Examining individual differences in reward responsiveness of the domestic dog.
Although there is ample data indicating that reward processing plays an important role in human psychopathologies and pharmaco- and psychotherapy treatment response, the corresponding animal-model research needs to be extended to models whose motivational and social dispositions are better generalizable than those of the traditional models. Accordingly, our aim was to develop and assess the reliability and validity of an owner-report rating scale of reward responsiveness in domestic dogs (N = 2149) and then to examine individual differences in reward responsiveness. Responsiveness was categorisable by reward type (ball/toy and food) and exhibited individual variability manifesting in age- and breed-related differences. Rating scale scores were associated with behavioural observation of reward processing, indicating evidence of convergent validity. Ball/toy and food reward responsiveness were associated with owner-rated hyperactivity-impulsivity' inattention and with differences in training, indicating evidence of concurrent validity. Extreme (vs. average) reward responsiveness was also predicted by dogs' hyperactivity-impulsivity and inattention' and extreme responsiveness was associated with increased likelihood of physical health and/or social problems. These findings are informative with regard to the dog as an animal model for various human behavioural and cognitive functions' and also for the dog in its own right as they are relevant to training and welfare.
CognitiveConstruct
RewardProcessing
29,520,717
10.1007/s11920-018-0877-z
2,018
Current psychiatry reports
Curr Psychiatry Rep
Presentation and Neurobiology of Anhedonia in Mood Disorders: Commonalities and Distinctions.
To focus on the clinical and behavioral presentation of anhedonia in mood disorders, as well as the differences and commonalities in the underlying neurocircuitry. Evidence suggests that depression is characterized by hypofunction of the reward system, while bipolar disorder manifests dysregulation of the behavioral activation system that increases goal-directed reward behavior. Importantly, strong evidence does not exist to suggest significant differences in anhedonia severity between depressed unipolar and bipolar patients, suggesting that there are more nuanced fluctuations in reward processing deficits in bipolar patients depending on their state. Both euthymic unipolar and bipolar patients frequently report residual reward dysfunction, which highlights the potential of reward processing deficits that give rise to the clinical symptom of anhedonia to be trait factors of mood disorders; however, the possibility that therapies are not adequately treating anhedonia could also explain the presence of residual symptoms. Reward processing represents a potential diagnostic and treatment marker for mood disorders. Further research should systematically explore the facets of reward processing in at-risk, affected, and remitted patients.
CognitiveConstruct
RewardProcessing
29,519,128
10.1177/0004867418761578
2,019
The Australian and New Zealand journal of psychiatry
Aust N Z J Psychiatry
Cumulative childhood interpersonal trauma is associated with reduced cortical differentiation between threat and non-threat faces in posttraumatic stress disorder adults.
Posttraumatic stress disorder and childhood trauma frequently co-occur. Both are associated with abnormal neural responses to salient emotion stimuli. As childhood trauma is a risk factor for posttraumatic stress disorder, differentiating between their neurophysiological effects is necessary to elucidate the neural pathways by which childhood trauma exposure contributes to increased posttraumatic stress disorder risks. Face-specific N170 evoked response potentials for backward-masked (non-conscious) and conscious threat (fear, angry) and non-threat (happy) faces were measured in 77 adults (18-64 years old, 64% women, 78% right-handed) symptomatic for posttraumatic stress disorder. Differences in N170 peak amplitudes for fear-versus-happy and angry-versus-happy faces at bilateral temporo-occipital (T5, T6) sites were computed. The effect of cumulative exposure to childhood interpersonal trauma, other childhood trauma, adult trauma, depression and posttraumatic stress disorder symptom severity on the N170 response was assessed using hierarchical multiple regression analyses. T5 N170 peak amplitudes for non-conscious fear-versus-happy faces were inversely related to cumulative childhood interpersonal trauma after accounting for socio-demographic, clinical symptom and other trauma factors. Posttraumatic stress disorder Avoidance was positively associated with N170 peak amplitudes for non-conscious fear-versus-happy faces, primarily due to reduced N170 responsivity to happy faces. Childhood interpersonal trauma exposure is associated with reduced discrimination between fear and happy faces, while avoidance symptom severity is associated with dampened responsivity to automatically processed happy faces in posttraumatic stress disorder adults. Results are discussed in terms of the likely contributions of impaired threat discrimination and deficient reward processing during neural processing of salient emotion stimuli, to increased risks of posttraumatic stress disorder onset and chronicity in childhood interpersonal trauma-exposed adults.
CognitiveConstruct
RewardProcessing
29,515,787
10.18632/oncotarget.24245
2,018
Oncotarget
Oncotarget
Effect of traumatic brain injury on nicotine-induced modulation of dopamine release in the striatum and nucleus accumbens shell.
Traumatic brain injury is associated with substantial alterations in reward processing, but underlying mechanisms are controversial. A better understanding of alterations in dopamine (DA) release patterns from the dorsal striatum and nucleus accumbens shell (NAc) may provide insights into posttraumatic reward pathology. The patterns of DA release with or without exposure to nicotine in brain slices with striatum and NAc, isolated from Sprague-Dawley rats with 6 psi fluid percussion (FPI) or sham injury were analysis by using fast-scan cyclic voltammetry. Tonic and phasic DA releases were assessed using single pulse and 10 pulses at 25 Hz, respectively. DA release relative to stimulation intensity, frequency, number of pulses, and paired-pulse facilitation was evaluated to determine release probability and response to bursting. There was a profound suppression in tonic DA release after nicotine desensitization after FPI, and the input/output curve for the DA release based on stimulation intensity was shifted to the right. FPI was associated with a significant decrease in frequency-dependent DA release augmentation, DA release induced by high frequency stimulation trains, and DA release in response to paired-pulse facilitation. The effect of nicotine desensitization was similar in FPI and sham-injured animals, although significantly smaller after FPI. Nicotine desensitization-induced differences between phasic and tonic release concentrations that contrasted with the reward-related signals then became less prominent in NAc after FPI. TBI blunts DA release from mesolimbic reward centers, and more intense stimuli are required to produce context-dependent DA release sufficient to have a physiological effect. The nicotine desensitization-related suppression in tonic DA release was profound with right-ward shift of the input/output curve for DA release after FPI. FPI was associated with a significant decrease in frequency-dependent DA release augmentation, DA release induced by high frequency stimulation trains, and DA release in response to paired-pulse facilitation. Nicotine desensitization-induced differences between phasic and tonic release concentrations that contrasted with the reward-related signals then became less prominent in NAc after FPI. TBI thus blunts DA release from mesolimbic reward centers, and more intense stimuli are required to produce context-dependent DA release sufficient to have a physiological effect.
CognitiveConstruct
RewardProcessing
29,503,842
10.1016/j.cobeha.2018.01.024
2,018
Current opinion in behavioral sciences
Curr Opin Behav Sci
Anhedonia in depression: biological mechanisms and computational models.
Anhedonia is a severe condition that describes a near-complete absence of enjoyment, motivation, and interest. A core feature of depression, clinical manifestations of anhedonia can include deficits in experiencing pleasure, approach-related motivated behavior, and learning how to match expectations to the environment. To date, the precise neurobiological mechanisms of anhedonia in major depression are still poorly understood. We have previously argued that contradictory findings and the inability to identify specific neurobiological substrates for anhedonic symptoms may result from sample heterogeneity, suboptimal methods of assessment, and the challenge of dissociating between different components of anhedonia. Recently, however, computational advances to the operationalization of psychiatric symptoms have enhanced the ability to evaluate the neurobiology of constituent elements of this symptom domain. In this paper, we review (1) advances in behavioral and computational methods of assessing reward processing and motivation and (2) the development of new self-report, neurological, and biological methods of subtyping that may be useful in future pursuits to expand our understanding of the neurobiology of anhedonia in depression.
CognitiveConstruct
RewardProcessing
29,502,949
10.1016/j.cub.2018.01.081
2,018
Current biology : CB
Curr Biol
Spatial Rule Learning and Corresponding CA1 Place Cell Reorientation Depend on Local Dopamine Release.
Incentives drive goal-directed behavior; however, how they impact the formation and stabilization of goal-relevant hippocampal maps remains unknown. Since dopamine is involved in reward processing, affects hippocampal-dependent behavior, and modulates hippocampal plasticity, we hypothesized that local dopaminergic transmission in the hippocampus serves to mold the formation and updating of hippocampal cognitive maps to adaptively represent reward-predicting space of sensory inputs. We recorded CA1 place cells of rats throughout training on a spatial extra-dimensional set-shift task. After learning to rely on one of two orthogonal sets of cues, we introduced a rule shift and infused locally the D receptor (DR) antagonist SCH23390. Successful learning was accompanied by place cell reorientation to represent rule-relevant spatial dimension. SCH23390 infusion prevented this remapping and, consequently, impaired learning, causing perseveration. These findings suggest that dopaminergic innervation provides reward information to the hippocampus and is critical for the stabilization of goal-related hippocampal representation, contributing to successful goal-directed behavior.
CognitiveConstruct
RewardProcessing
29,500,671
10.1007/s11695-018-3178-z
2,018
Obesity surgery
Obes Surg
Sleeve Gastrectomy Recovering Disordered Brain Function in Subjects with Obesity: a Longitudinal fMRI Study.
Bariatric surgery could recover regional dysfunction of cerebral cortex. However, it is unknown whether bariatric surgery could recover the global-level dysfunction in subjects with obesity. The aim of this study was to investigate the effect of bariatric surgery on global-level dysfunction in subjects with obesity by resting-state functional magnetic resonance imaging (fMRI). Resting-state fMRI was used to investigate dysfunction of whole-brain in 34 subjects with obesity and 34 age-and gender-matched normal-weight subjects, in which 17 subjects with obesity received sleeve gastrectomy. Fractional amplitude of low-frequency fluctuation (fALFF) and functional connectivity (FC) among the whole brain were used to estimate the brain functional differences among the preoperative subjects, postoperative subjects, and the controls. The preoperative subjects compared to controls had decreased resting-state activities in reward processing and cognitive control regions such as orbitofrontal cortex, middle frontal gyrus, superior frontal gyrus, and gyrus rectus. It was important that increased FC was also found in these regions. Correlation analysis showed that body mass index (BMI) was associated with these decreased activity and increased FC. More importantly, the dysfunction in these regions was recovered by the bariatric surgery. These results suggest that bariatric surgery-induced weight loss could reverse the global-level dysfunction in subjects with obesity. The dysfunction in these regions might play a key role in the development of obesity, which might serve as a biomarker in the treatment of obesity.
CognitiveConstruct
RewardProcessing
29,497,369
10.3389/fnhum.2018.00051
2,018
Frontiers in human neuroscience
Front Hum Neurosci
Reduced Orbitofrontal Gray Matter Concentration as a Marker of Premorbid Childhood Trauma in Cocaine Use Disorder.
: Childhood trauma affects neurodevelopment and promotes vulnerability to impaired constraint, depression, and addiction. Reduced gray matter concentration (GMC) in the mesocorticolimbic regions implicated in reward processing and cognitive control may be an underlying substrate, as documented separately in addiction and for childhood trauma. The purpose of this study was to understand the contribution of childhood maltreatment to GMC effects in individuals with cocaine use disorder. : Individuals with cocaine use disorder were partitioned into groups of low vs. high childhood trauma based on median split of the total score of the Childhood Trauma Questionnaire (CTQ; CUD-L, = 23; CUD-H, = 24) and compared with age, race, and gender matched healthy controls with low trauma ( = 29). GMC was obtained using voxel-based morphometry applied to T1-weighted MRI scans. Drug use, depression and constraint were assessed with standardized instruments. : Whole-brain group comparisons showed reduced GMC in the right lateral orbitofrontal cortex (OFC) in CUD-H as compared with controls (cluster-level < 0.001) and CUD-L (cluster-level = 0.035); there were no significant differences between CUD-L and controls. A hierarchical regression analysis across both CUD groups revealed that childhood trauma, but not demographics and drug use, and beyond constraint and depression, accounted for 37.7% of the variance in the GMC in the right lateral OFC ( < 0.001). : Beyond other contributing factors, childhood trauma predicted GMC reductions in the OFC in individuals with cocaine use disorder. These findings underscore a link between premorbid environmental stress and morphological integrity of a brain region central for behaviors underlying drug addiction. These results further highlight the importance of accounting for childhood trauma, potentially as a factor predisposing to addiction, when examining and interpreting neural alterations in cocaine addicted individuals.
CognitiveConstruct
RewardProcessing
29,496,610
10.1016/j.neuroimage.2018.02.049
2,018
NeuroImage
Neuroimage
Integration of reward with cost anticipation during performance monitoring revealed by ERPs and EEG spectral perturbations.
Effort expenditure has an aversive connotation and it can lower hedonic feelings. In this study, we explored the electrophysiological correlates of the complex interplay of reward processing with cost anticipation. To this aim, healthy adult participants performed a gambling task where the outcome (monetary reward vs. no-reward) and its expectancy were manipulated on a trial by trial basis while 64-channel EEG was recorded. Crucially, on some trials, the no-reward outcome could be transformed to a rewarding one, pending effort expenditure by means of an orthogonal dot clicking task, enabling us to compare at the electrophysiological level reward processing when cost was anticipated or not. We extracted and compared different markers of reward processing at the feedback level using both classical ERPs and EEG spectral perturbations in specific bands (theta, delta and beta-gamma). At the behavioral level, participants reported enhanced pleasure and relief when the outcome was rewarding but effort expenditure could be avoided, relative to a control condition where the outcome was rewarding but no extra effort was anticipated. In this condition, EEG results showed a larger Reward Positivity ERP component and increased power in the Delta and Beta-gamma bands. By comparison, cost anticipation did not influence the processing of the no-reward outcome at the FRN and frontal midline theta levels. All together, these neurophysiological results suggest that effort avoidance is associated with increased reward processing.
CognitiveConstruct
RewardProcessing
29,486,870
10.1016/j.bpsc.2017.11.004
2,018
Biological psychiatry. Cognitive neuroscience and neuroimaging
Biol Psychiatry Cogn Neurosci Neuroimaging
Subcortical Local Functional Hyperconnectivity in Cannabis Dependence.
Cannabis abuse (CA) has been associated with psychopathology, including negative emotionality and higher risk of psychosis, particularly with early age of initiation. However, the mechanisms underlying this association are poorly understood. Because aberrant dopamine signaling is implicated in cannabis-associated psychopathology, we hypothesized that regular CA would be associated with altered resting-state functional connectivity in dopamine midbrain-striatal circuits. We examined resting-state brain activity of subcortical regions in 441 young adults from the Human Connectome Project, including 30 subjects with CA meeting DSM-IV criteria for dependence and 30 control subjects matched on age, sex, education, body mass index, anxiety, depression, and alcohol and tobacco usage. Across all subjects, local functional connectivity density hubs in subcortical regions were most prominent in ventral striatum, hippocampus, amygdala, dorsal midbrain, and posterior-ventral brainstem. As hypothesized, subjects with CA showed markedly increased local functional connectivity density relative to control subjects, not only in ventral striatum (where nucleus accumbens is located) and midbrain (where substantia nigra and ventral tegmental nuclei are located) but also in brainstem and lateral thalamus. These effects were observed in the absence of significant differences in subcortical volumes and were most pronounced in individuals who began cannabis use earliest in life and who reported high levels of negative emotionality. Together, these findings suggest that chronic CA is associated with changes in resting-state brain function, particularly in dopaminergic nuclei implicated in psychosis but that are also critical for habit formation and reward processing. These results shed light on neurobiological differences that may be relevant to psychopathology associated with cannabis use.
CognitiveConstruct
RewardProcessing
29,483,346
10.1098/rstb.2017.0161
2,018
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
Philos Trans R Soc Lond B Biol Sci
The functional highly sensitive brain: a review of the brain circuits underlying sensory processing sensitivity and seemingly related disorders.
During the past decade, research on the biological basis of sensory processing sensitivity (SPS)-a genetically based trait associated with greater sensitivity and responsivity to environmental and social stimuli-has burgeoned. As researchers try to characterize this trait, it is still unclear how SPS is distinct from seemingly related clinical disorders that have overlapping symptoms, such as sensitivity to the environment and hyper-responsiveness to incoming stimuli. Thus, in this review, we compare the neural regions implicated in SPS with those found in fMRI studies of-Autism Spectrum Disorder (ASD), Schizophrenia (SZ) and Post-Traumatic Stress Disorder (PTSD) to elucidate the neural markers and cardinal features of SPS versus these seemingly related clinical disorders. We propose that SPS is a stable trait that is characterized by greater empathy, awareness, responsivity and depth of processing to salient stimuli. We conclude that SPS is distinct from ASD, SZ and PTSD in that in response to social and emotional stimuli, SPS differentially engages brain regions involved in reward processing, memory, physiological homeostasis, self-other processing, empathy and awareness. We suggest that this serves species survival via deep integration and memory for environmental and social information that may subserve well-being and cooperation.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.
CognitiveConstruct
RewardProcessing
29,477,609
10.1016/j.nlm.2018.02.026
2,018
Neurobiology of learning and memory
Neurobiol Learn Mem
Learning what to expect and when to expect it involves dissociable neural systems.
Two experiments with Long-Evans rats examined the potential independence of learning about different features of food reward, namely, "what" reward is to be expected and "when" it will occur. This was examined by investigating the effects of selective reward devaluation upon responding in an instrumental peak timing task in Experiment 1 and by exploring the effects of pre-training lesions targeting the basolateral amygdala (BLA) upon the selective reward devaluation effect and interval timing in a Pavlovian peak timing task in Experiment 2. In both tasks, two stimuli, each 60 s long, signaled that qualitatively distinct rewards (different flavored food pellets) could occur after 20 s. Responding on non-rewarded probe trials displayed the characteristic peak timing function with mean responding gradually increasing and peaking at approximately 20 s before more gradually declining thereafter. One of the rewards was then independently paired repeatedly with LiCl injections in order to devalue it whereas the other reward was unpaired with these injections. In a final set of test sessions in which both stimuli were presented without rewards, it was observed that responding was selectively reduced in the presence of the stimulus signaling the devalued reward compared to the stimulus signaling the still valued reward. Moreover, the timing function was mostly unaltered by this devaluation manipulation. Experiment 2 showed that pre-training BLA lesions abolished this selective reward devaluation effect, but it had no impact on peak timing functions shown by the two stimuli. It appears from these data that learning about "what" and "when" features of reward may entail separate underlying neural systems.
CognitiveConstruct
RewardProcessing
29,471,098
10.1016/j.neuroimage.2018.02.039
2,018
NeuroImage
Neuroimage
The role of effective connectivity between the task-positive and task-negative network for evidence gathering [Evidence gathering and connectivity].
Reports linking a 'jumping-to-conclusions' bias to delusions have led to growing interest in the neurobiological correlates of probabilistic reasoning. Several brain areas have been implicated in probabilistic reasoning; however, findings are difficult to integrate into a coherent account. The present study aimed to provide additional evidence by investigating, for the first time, effective connectivity among brain areas involved in different stages of evidence gathering. We investigated evidence gathering in 25 healthy individuals using fMRI and a new paradigm (Box Task) designed such as to minimize the effects of cognitive effort and reward processing. Decisions to collect more evidence ('draws') were contrasted to decisions to reach a final choice ('conclusions') with respect to BOLD activity. Psychophysiological interaction analysis was used to investigate effective connectivity. Conclusion events were associated with extensive brain activations in widely distributed brain areas associated with the task-positive network. In contrast, draw events were characterized by higher activation in areas assumed to be part of the task-negative network. Effective connectivity between the two networks decreased during draws and increased during conclusion events. Our findings indicate that probabilistic reasoning may depend on the balance between the task-positive and task-negative network, and that shifts in connectivity between the two may be crucial for evidence gathering. Thus, abnormal connectivity between the two systems may significantly contribute to the jumping-to-conclusions bias.
CognitiveConstruct
RewardProcessing