Imager-A mobile health mental imagery-based ecological momentary intervention targeting reward sensitivity: A randomized controlled trial

Robust reward sensitivity may help preserve mental well-being in the face of adversity and has been proposed as a key stress resilience factor. Here, we present a mobile health application, "Imager," which targets reward sensitivity by training individuals to create mental images of future rewarding experiences. We conducted a two-arm randomized controlled trial with 95 participants screened for reward sensitivity. Participants in the intervention group received an ecological momentary intervention-Imager, which encouraged participants to create mental images of rewarding events for 1 week. The control group participants received only ecological momentary assessment, without the instruction to generate mental images. Adherence to Imager was high; participants in the intervention group engaged in 88% of the planned activities. In the follow-up assessment, the intervention group reported less mental health symptoms, mainly in depression (β = -0.34, df = 93, p = .004) and less perceived stress (β = -0.18, df = 93, p = .035), than control group participants and compared with the baseline assessment. Our results show the positive effects of Imager on mental health symptoms. The encouraging effects of the app on mental health outcomes may lead to greater use of ecological momentary interventions in the clinical preventive practice of affective disorders.

Smoking Progression and Nicotine-Enhanced Reward Sensitivity Predicted by Resting-State Functional Connectivity in Salience and Executive Control Networks

INTRODUCTION

The neural underpinnings underlying individual differences in nicotine-enhanced reward sensitivity and smoking progression are poorly understood. Thus, we investigated whether brain resting-state functional connectivity (rsFC) during smoking abstinence predicts nicotine-enhanced reward sensitivity and smoking progression in young light smokers. We hypothesized that high rsFC between brain areas with high densities of nicotinic receptors (insula, anterior cingulate cortex [ACC], hippocampus, thalamus) and areas involved in reward-seeking (nucleus accumbens [NAcc], prefrontal cortex [PFC]) would predict nicotine-enhanced reward sensitivity and smoking progression.

METHODS

Young light smokers (N=64, age 18-24, M = 1.89 cigarettes/day) participated in the study. These individuals smoked between 5 to 35 cigarettes per week and lifetime use never exceeded 35 cigarettes per week. Their rsFC was assessed using functional magnetic resonance imaging after 14-hour nicotine-deprivation. Subjects also completed a probabilistic reward task after smoking a placebo on one day and a regular cigarette on another day.

RESULTS

The probabilistic-reward-task assessed greater nicotine-enhanced reward sensitivity was associated with greater rsFC between the right anterior PFC and right NAcc, but with reduced rsFC between the ACC and left inferior prefrontal gyrus and the insula and ACC. Decreased rsFC within the salience network (ACC and insula) predicted increased smoking progression across 18 months and greater nicotine-enhanced reward sensitivity.

CONCLUSIONS

These findings provide the first evidence that differences in rsFCs in young light smokers are associated with nicotine-enhanced reward sensitivity and smoking progression.

IMPLICATIONS

Weaker rsFC within the salience network predicted greater nicotine-enhanced reward sensitivity and smoking progression. These findings suggest that salience network rsFC and drug-enhanced reward sensitivity may be useful tools and potential endophenotypes for reward sensitivity and drug-dependence research.

Change in motivational bias during treatment predicts outcome in anorexia nervosa

OBJECTIVE

Reward and punishment sensitivity are known to be altered in anorexia nervosa (AN). Most research has examined these constructs separately although motivated behavior is influenced by considering both the potential for reward and risk of punishment. The present study sought to compare the relative balance of reward and punishment sensitivity in AN versus healthy controls (HCs) and examine whether motivational bias is associated with AN symptoms and treatment outcomes.

METHODS

Adolescents and adults with AN (n = 262) in a partial hospitalization program completed the Eating Disorders Examination Questionnaire (EDE-Q), Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scales, and Sensitivity to Punishment/Sensitivity to Reward Questionnaire (SPSRQ) at admission and discharge. HCs (HC; n = 90) completed the BIS/BAS and SPSRQ. Motivational Bias Scores were calculated to reflect the dominance of reward versus punishment sensitivity.

RESULTS

Individuals with AN demonstrated significantly greater bias toward punishment sensitivity than HC. In AN, a bias toward punishment was associated with higher EDE-Q Global score at admission. Change in motivational bias during treatment predicted EDE-Q Global scores, but not BMI, at discharge, with greater increases in reward sensitivity or greater decreases in punishment sensitivity during treatment predicting lower eating pathology. Similar findings were observed using the BIS/BAS and SPSRQ.

DISCUSSION

Change in motivational bias during treatment is associated with improved outcomes in AN. However, it appears that much of the change in motivational bias can be attributed to changes in punishment sensitivity, rather than reward sensitivity. Future research should examine the mechanisms underlying punishment sensitivity decreases during treatment.

PUBLIC SIGNIFICANCE

Sensitivity to reward and punishment may be important treatment targets for individuals with anorexia nervosa (AN). To date, most research has considered reward and punishment sensitivity separately, rather than examining their relationship to each other. We found that the balance of reward and punishment sensitivity (i.e., motivational bias) differs between healthy controls and those with AN and that this bias is associated with eating disorder symptoms and treatment outcome.

Depression is associated with reduced outcome sensitivity in a dual valence, magnitude learning task

BACKGROUND

Learning from rewarded and punished choices is perturbed in depressed patients, suggesting that abnormal reinforcement learning may be a cognitive mechanism of the illness. However, previous studies have disagreed about whether this behavior is produced by alterations in the rate of learning or sensitivity to experienced outcomes. This previous work has generally assessed learning in response to binary outcomes of one valence, rather than to both rewarding and punishing continuous outcomes.

METHODS

A novel drifting reward and punishment magnitude reinforcement-learning task was administered to patients with current (n = 40) and remitted depression (n = 39), and healthy volunteers (n = 40) to capture potential differences in learning behavior. Standard questionnaires were administered to measure self-reported depressive symptom severity, trait and state anxiety and level of anhedonic symptoms.

RESULTS

Our findings demonstrate that patients with current depression adjust their learning behaviors to a lesser degree in response to trial-by-trial variations in reward and loss magnitudes than the other groups. Computational modeling revealed that this behavioral signature of current depressive state is better accounted for by reduced reward and punishment sensitivity (all p < 0.031), rather than a change in learning rate (p = 0.708). However, between-group differences were not related to self-reported symptom severity or comorbid anxiety disorders in the current depression group.

CONCLUSION

These findings suggest that current depression is associated with reduced outcome sensitivity rather than altered learning rate. Previous findings reported in this domain mainly from binary learning tasks seem to generalize to learning from continuous outcomes.

Heterogeneity of gaming disorder: A clinically-based typology for developing personalized interventions

Background

The eleventh revision of the International Classification of Diseases (ICD-11) defines the three key diagnostic criteria for gaming disorder (GD). These are loss of control over gaming, gaming as a priority over daily activities, and impaired functioning due to gaming. While this definition has implications for the prevention and treatment of GD, there is significant heterogeneity in the symptoms and etiology of GD among individuals, which results in different treatment needs. Cognitive control, emotional regulation, and reward sensitivity are three critical dimensions in the etiology model for GD. Aspects such as gender, comorbidity, motivation for gaming, stage or severity of GD, and risk factors all contribute to the heterogeneity of etiology among individuals with the disorder.

Method

On the basis of clinical symptoms and comorbidity characteristics among approximately 400 patients with gaming disorder, the present paper proposes a clinical typology of patients with GD based on the authors' clinical experience in treating individuals with GD.

Results

The findings indicated three common types of patients with GD: (i) impulsive male patients with attention deficit hyperactivity disorder (ADHD), (ii) dysphoria patients with dysfunctional coping skills, and (iii) isolated patients with social anxiety. The paper also discusses the presentation and treatment priority for these patients.

Conclusion

Personalized treatments for patients with GD should be developed to fit their individual needs. Future studies should examine the heterogeneity of GD and confirm these types, as well as obtain evidence-based information that can help in the development of personalized treatment. Treatment resources should be developed, and professionals should be trained to provide integrated individualized treatment.

The association between delinquent peer affiliation and disruptive behavior interacts with functional brain correlates of reward sensitivity: a biosocial interaction study in adolescent delinquents

BACKGROUND

Affiliating with delinquent peers may stimulate the development of antisocial behavior, especially for adolescents who are sensitive to social rewards. The current study examines whether the association between delinquent peer affiliation (DPA) and disruptive behavior interacts with functional brain correlates of reward sensitivity in early onset male adolescents delinquents.

METHODS

Childhood arrestees (n = 126, mean age = 17.7 [s.d. 1.6]) completed a DPA questionnaire, and participated in an fMRI study in which reward sensitivity was operationalized through responsiveness of the ventral striatum (VS), amygdala, and medial prefrontal cortex (mPFC) during the monetary incentive delay paradigm (reward anticipation and outcome). Symptoms of disruptive behavior disorders (DBD) were assessed through structured psychiatric interviews (Diagnostic Interview Schedule for Children) with adolescents.

RESULTS

DPA had a main effect on DBD symptoms. Adolescents with high VS reward responses showed a stronger significant positive association between DPA and DBD symptoms compared to low VS responders. No evidence for an interaction effect was found for the amygdala and mPFC. Post-hoc analyses revealed the positive association between DPA and DBD was only present in males, with a diminishing effect as age increased.

CONCLUSIONS

We found evidence for a biosocial interaction between DPA and reward sensitivity of the VS in relation to DBD symptom severity. This study provides the first evidence of an interaction effect between a brain mechanism and an environmental factor in relation to DBD symptoms, implying that susceptibility to influences of delinquent peers may intertwine with individual biological differences.

Neural response to rewards moderates the within-person association between daily positive events and positive affect during a period of stress exposure

Stress and neural responses to reward can interact to predict psychopathology, but the mechanisms of this interaction are unclear. One possibility is that the strength of neural responses to reward can affect the ability to maintain positive affect during stress. In this study, 105 participants completed a monetary reward task to elicit the reward positivity (RewP), an event-related potential sensitive to rewards. Subsequently, during a stressful period, participants reported on their affect nine times a day and on daily positive and negative events for 10 days. Even during heightened stress, experiencing more positive events was associated with increased positive affect. The RewP significantly moderated this association: Individuals with a larger RewP reported greater increases in positive affect when they experienced more positive events, relative to individuals with a smaller RewP. A blunted RewP might contribute to stress susceptibility by affecting how much individuals engage in positive emotion regulation during stress.

Exploratory study of the prevalence of food addiction and its relationship with executive functioning, depression, and reinforcement sensitivity in a sample of Mexican adults

Introduction

The study of food addiction (FA) has become relevant due to its high prevalence, the negative impact on quality of life, and its association with neuropsychological and psychiatric symptoms. Several studies have provided scientific support for these associations, however, the results are contradictory. Additionally, studies have unsuccessfully elucidated the true nature of the failures in executive functioning in people with FA symptomatology, particularly when it comes to executive deficits. Therefore, the purpose of this research was to establish whether the presence of executive dysfunction, depressive symptoms and binge eating problems, as well as high reward sensitivity entails a greater severity in FA traits and high body mass index (BMI) in a sample of Mexican adults.

Methods

The sample consisted of Mexican men and women between 21-59 years (n = 36); who completed self-report questionnaires and performance tests to measure the study variables. Additionally, BMI was estimated with self-reported height and weight.

Results

Our results showed that a high number of FA symptoms were associated with higher executive dysfunction scores, greater reward sensitivity, and more severe depressive and binge eating problems. Furthermore, factors that are more strongly associated with higher scores of FA include severe executive deficits, greater activation of the punishment avoidance system, and persistence in the search for reward when the depressive symptoms increased. The factors that best explained changes in the estimated BMI of women were a decreased crystallized intellectual capacity and the inability to control food intake as the number of FA symptoms increased.

Discussion

In summary, the cognitive functioning profile characterized by general failure of the executive functioning, as well as a greater activation of the Punishment Avoidance System and persistence in the search for reward, were associated with greater severity of FA symptoms, especially when the depressive symptomatology was severe. In parallel, the psychopathology in participants associated with FA confirms the contribution of anxious and depressive symptomatology and borderline personality traits which could facilitate the expression of clinically relevant FA symptoms in women. Finally, we found that decreased crystallized intellectual capacity and inability to control food intake were linked to higher BMI when the number of FA symptoms increased.

Contribution of the Roman rat lines/strains to personality neuroscience: neurobehavioral modeling of internalizing/externalizing psychopathologies

The Roman high-avoidance (RHA) and low-avoidance (RLA) rat lines/strains were established in Rome through bidirectional selection of Wistar rats for rapid (RHA) or extremely poor (RLA) acquisition of a two-way active avoidance task. Relative to RHAs, RLA rats exhibit enhanced threat sensitivity, anxiety, fear and vulnerability to stress, a passive coping style and increased sensitivity to frustration. Thus, RLA rats' phenotypic profile falls well within the "internalizing" behavior spectrum. Compared with RLAs and other rat strains/stocks, RHAs present increased impulsivity and reward sensitivity, deficits in social behavior and attentional/cognitive processes, novelty-induced hyper-locomotion and vulnerability to psychostimulant sensitization and drug addiction. Thus, RHA rats' phenotypes are consistent with a "disinhibiting externalizing" profile. Many neurobiological/molecular traits differentiate both rat lines/strains. For example, relative to RLA rats, RHAs exhibit decreased function of the prefrontal cortex (PFC), hippocampus and amygdala, increased functional tone of the mesolimbic dopamine system, a deficit of central metabotropic glutamate-2 (mGlu2) receptors, increased density of serotonin 5-HT2A receptors in the PFC, impairment of GABAergic transmission in the PFC, alterations of several synaptic markers and increased density of pyramidal immature dendrític spines in the PFC. These characteristics suggest an immature brain of RHA rats and are reminiscent of schizophrenia features like hypofrontality and disruption of the excitation/inhibition cortical balance. We review evidence supporting RLA rats as a valid model of anxiety/fear, stress and frustration vulnerability, whereas RHA rats represent a promising translational model of neurodevelopmental alterations related to impulsivity, schizophrenia-relevant features and comorbidity with drug addiction vulnerability.

Support from a Best Friend Makes People Eat Less under Stress: Evidence from Two Experiments

When experiencing acute stress, individuals often turn to eating for comfort, as it provides a sense of satiety and satisfaction that can temporarily alleviate the stressful condition. However, this may increase the risk of obesity, diabetes, cardiovascular disease. In this study, we conducted two behavioral experiments to investigate the effectiveness of social support in reducing stress-induced overeating and the mediative role of negative affect and self-efficacy (Experiment 1), as well as the role of reward sensitivity (Experiment 2). Acute stress was induced using a speech preparation task and then participants were asked to regulate their emotions and cognition, either alone or with the help of pictures and supportive sentences provided by a best friend or stranger. Participants in Experiment 1 then completed the food choice task, and participants in Experiment 2 completed the food incentive delay task and the bogus tasting task. The results of both experiments consistently showed that participants who received support from their friends reported lower levels of perceived stress, chose fewer food portions, and consumed fewer snacks during acute stress, compared to the other three groups. Further mediation analysis using the process macro revealed that the differential influence of social support on the choice of high-calorie foods was due to decreased negative affect and increased self-efficacy. This study provides valuable insights for the development of therapeutic interventions for clinical eating disorders.

Facets of impulsivity and reward in relation to binge-eating disorder course of illness among children: findings from the Adolescent Brain Cognitive Development study

BACKGROUND

The present study examined facets of impulsivity and reward sensitivity [as measured by the UPPS-P Impulsive Behavior Scale and Behavioral Activation and Behavioral Inhibition Scales (BIS/BAS)] as multivariable predictors of subsequent binge-eating disorder (BED) course of illness in middle childhood.

METHODS

The current sample included children aged 9-10 years (N = 9,438) who took part in the baseline and 1-year follow-up assessments of the Adolescent Brain Cognitive Development (ABCD) study. BED course was operationalized as those who never developed BED or subthreshold BED (SBED) ('control'), were diagnosed with BED/SBED at year 1 but not baseline ('developers'), were diagnosed with BED/SBED at baseline but not year 1 ('remitters'), or were diagnosed with BED/SBED at both times ('maintainers').

RESULTS

Higher baseline BIS/BAS reward responsivity scores were related to the greater likelihood of belonging to the maintainer group relative to the control and remitter groups (ORs1.12-1.19). Regarding covariates, higher baseline body mass index percentile and internalizing symptoms were related to the greater likelihood of BED development, remittance, and maintenance compared to the control group (ORs = 1.04-1.14); no variables were uniquely related to BED development. Exploratory analyses showed that the likelihood of belonging to the maintainer group compared to the control group was greatest at higher levels of negative urgency in combination with high reward responsivity.

CONCLUSIONS

Heightened reward responsivity may convey risk for poorer BED course in children, while emotional disorder symptomatology may act as a more general risk and maintenance factor for BED.

Aberrant functional connectivity between reward and inhibitory control networks in pre-adolescent binge eating disorder

BACKGROUND

Behavioral features of binge eating disorder (BED) suggest abnormalities in reward and inhibitory control. Studies of adult populations suggest functional abnormalities in reward and inhibitory control networks. Despite behavioral markers often developing in children, the neurobiology of pediatric BED remains unstudied.

METHODS

58 pre-adolescent children (aged 9-10-years) with BED (mBMI = 25.05; s.d. = 5.40) and 66 age, BMI and developmentally matched control children (mBMI = 25.78; s.d. = 0.33) were extracted from the 3.0 baseline (Year 0) release of the Adolescent Brain Cognitive Development (ABCD) Study. We investigated group differences in resting-state functional MRI functional connectivity (FC) within and between reward and inhibitory control networks. A seed-based approach was employed to assess nodes in the reward [orbitofrontal cortex (OFC), nucleus accumbens, amygdala] and inhibitory control [dorsolateral prefrontal cortex, anterior cingulate cortex (ACC)] networks via hypothesis-driven seed-to-seed analyses, and secondary seed-to-voxel analyses.

RESULTS

Findings revealed reduced FC between the dlPFC and amygdala, and between the ACC and OFC in pre-adolescent children with BED, relative to controls. These findings indicating aberrant connectivity between nodes of inhibitory control and reward networks were corroborated by the whole-brain FC analyses.

CONCLUSIONS

Early-onset BED may be characterized by diffuse abnormalities in the functional synergy between reward and cognitive control networks, without perturbations within reward and inhibitory control networks, respectively. The decreased capacity to regulate a reward-driven pursuit of hedonic foods, which is characteristic of BED, may in part, rest on this dysconnectivity between reward and inhibitory control networks.

Contextualizing the Neural Vulnerabilities Model of Obesity

In recent years, investigators have focused on neural vulnerability factors that increase the risk of unhealthy weight gain, which has provided a useful organizing structure for obesity neuroscience research. However, this framework, and much of the research it has informed, has given limited attention to contextual factors that may interact with key vulnerabilities to impact eating behaviors and weight gain. To fill this gap, we propose a Contextualized Neural Vulnerabilities Model of Obesity, extending the existing theory to more intentionally incorporate contextual factors that are hypothesized to interact with neural vulnerabilities in shaping eating behaviors and weight trajectories. We begin by providing an overview of the Neural Vulnerabilities Model of Obesity, and briefly review supporting evidence. Next, we suggest opportunities to add contextual considerations to the model, including incorporating environmental and developmental context, emphasizing how contextual factors may interact with neural vulnerabilities to impact eating and weight. We then synthesize earlier models and new extensions to describe a Contextualized Neural Vulnerabilities Model of Obesity with three interacting components-food reward sensitivity, top-down regulation, and environmental factors-all within a developmental framework that highlights adolescence as a key period. Finally, we propose critical research questions arising from the framework, as well as opportunities to inform novel interventions.

Sensitive caregiving and reward responsivity: A novel mechanism linking parenting and executive functions development in early childhood

Sensitive caregiving is an essential aspect of positive parenting that influences executive functions development, but the mechanisms underlying this association are less clear. Using data from the Family Life Project, a large prospective longitudinal sample of 1292 families residing in rural, predominately low-income communities, the current study examined whether sensitive caregiving impacts executive functions development by shaping behavioral reward processing systems in early postnatal life. Results indicated that higher levels of sensitive caregiving during infancy were associated with heightened reward responsivity at age 4, which in turn predicted superior executive functions ability at age 5. Notably, children's reward responsivity partially mediated the relationship between sensitive caregiving in infancy and executive functions ability at school entry. These findings add to prior work on early experience and children's executive functions and highlight caregiver scaffolding of developing reward processing systems as a potential foundational mechanism for supporting adaptive behavior and self-regulation across the lifespan.

Mood Symptom Dimensions and Developmental Differences in Neurocognition in Adolescence

Adolescence is critical period of neurocognitive development as well as increased prevalence of mood pathology. This cross-sectional study replicated developmental patterns of neurocognition and tested whether mood symptoms moderated developmental effects. Participants were 419 adolescents (n=246 with current mood disorders) who completed reward learning and executive functioning tasks, and reported on age, puberty, and mood symptoms. Structural equation modeling revealed a quadratic relationship between puberty and reward learning performance that was moderated by symptom severity: in early puberty, adolescents reporting higher manic symptoms exhibited heightened reward learning performance (better maximizing of rewards on learning tasks), whereas adolescents reporting elevated anhedonia showed blunted reward learning performance. Models also showed a linear relationship between age and executive functioning that was moderated by manic symptoms: adolescents reporting higher mania showed poorer executive functioning at older ages. Findings suggest neurocognitive development is altered in adolescents with mood pathology and suggest directions for longitudinal studies.

Impulsivity and reward sensitivity facets as predictors of weight change in children: Differences by binge-eating disorder diagnostic status

BACKGROUND

Impulsivity and reward sensitivity are personality traits associated with obesity and binge-eating disorder (BED), but little research has examined prospective associations between these traits and body mass index z-score (BMI-z) differentially for children with and without BED.

OBJECTIVE

Using data from the Adolescent Brain and Cognitive Development study, the present analysis examined predictive associations between impulsivity and reward sensitivity facets with BMI-z 1 year later in children with versus without BED.

METHODS

Nine-to-ten-year-old children were recruited across the United States and completed self-report questionnaires and clinical interviews at baseline, and height and weight were taken at baseline and 1-year follow-up. Multivariable models were run with baseline impulsivity and reward sensitivity facets predicting 1-year BMI-z in children with versus without BED.

RESULTS

Reward sensitivity and impulsivity were unrelated to BMI-z at follow-up in children without BED. Greater negative urgency (i.e., proclivity to act rashly without forethought in response to negative emotions) and lower positive urgency (i.e., proclivity to act rashly without forethought due to positive emotions) predicted increased BMI-z at 1-year follow-up in children with BED subsample.

CONCLUSIONS

Findings indicate the importance of developing theoretical models and interventions for obesity prevention in children with BED that address emotional impulsivity.

Fluoxetine degrades luminance perceptual thresholds while enhancing motivation and reward sensitivity

Selective serotonin reuptake inhibitors (SSRIs) increase serotonin activity in the brain. While they are mostly known for their antidepressant properties, they have been shown to improve visual functions in amblyopia and impact cognitive functions ranging from attention to motivation and sensitivity to reward. Yet, a clear understanding of the specific action of serotonin to each of bottom-up sensory and top-down cognitive control components and their interaction is still missing. To address this question, we characterize, in two adult male macaques, the behavioral effects of fluoxetine, a specific SSRI, on visual perception under varying bottom-up (luminosity, distractors) and top-down (uncertainty, reward biases) constraints while they are performing three different visual tasks. We first manipulate target luminosity in a visual detection task, and we show that fluoxetine degrades luminance perceptual thresholds. We then use a target detection task in the presence of spatial distractors, and we show that under fluoxetine, monkeys display both more liberal responses as well as a degraded perceptual spatial resolution. In a last target selection task, involving free choice in the presence of reward biases, we show that monkeys display an increased sensitivity to reward outcome under fluoxetine. In addition, we report that monkeys produce, under fluoxetine, more trials and less aborts, increased pupil size, shorter blink durations, as well as task-dependent changes in reaction times. Overall, while low level vision appears to be degraded by fluoxetine, performances in the visual tasks are maintained under fluoxetine due to enhanced top-down control based on task outcome and reward maximization.

Prenatal Caffeine Exposure Is Linked to Elevated Sugar Intake and BMI, Altered Reward Sensitivity, and Aberrant Insular Thickness in Adolescents: An ABCD Investigation

Prenatal caffeine exposure (PCE) has been positively associated with elevated body mass index (BMI) in children. Why this association occurs is unclear, but it is possible that PCE alters the in utero development of brain structures associated with food preference, leading to more total sugar intake (TSI, grams) later in childhood. To test this hypothesis, we investigated if PCE (daily/weekly/<weekly vs. no exposure) and elevated BMI are associated with increased TSI, neural activation during large reward anticipation (monetary incentive delay task—functional MRI) and structural changes (thickness, mm) in taste processing regions of children (n = 5534; 9−11 years) from the large-scale Adolescent Brain Cognitive Development (ABCD) study. Linear mixed-effect models, after covariate adjustments, identified a positive association (p < 0.05, all |βs| > 0.01) of excessive PCE (vs. no exposure) with elevated BMI (daily/weekly/daily limit; consistent in boys and girls), increased TSI (daily) and insular thickness (daily/weekly), as well as low middle frontal cortex (MFC) activation (daily). Our sub-analysis revealed an association of daily/weekly PCE (vs. no exposure) with increased gram sugar intake from soft drinks. We also identified a positive relationship of excessive PCE with elevated TSI and increased insular thickness (a key gustatory region), while in a Sobel test, reward sensitivity (reduced brain reactivity to reward anticipation in MFC; tracks reward outcomes) mediated (Test statistic = 2.23; p = 0.02) the PCE-linked BMI changes in adolescents. Our findings suggest that excessive PCE might be detrimental to frontal lobe development and altered reward sensitivity to food, thereby increasing risk for elevated TSI and obesity. Our results support recommendations to limit caffeine intake during pregnancy.

Effect of social instability stress in adolescence or adulthood on sensitivity to sucrose concentration in a social context in male and female Long-Evans rats

Although there is evidence of sex differences in responding to social stress, and that age when stressed matters, females are understudied and adult-stress comparisons are few. Here, we investigated stress effects on reward sensitivity by examining rats' choice of social versus sucrose reward in a continuous spatial allocation design. We predicted social instability stress (SS) in adolescence would result in greater social discounting (spend less time near a novel peer when provided access to sucrose) relative to nonstressed controls (CTLs) and relative to SS in adulthood. All increased sucrose intake as the concentration increased, with no evidence of social discounting. SS males tested soon after the stress had a decrease in intake, whereas those tested long after had an increase in both time near the peer and in intake. CTL and SS females did not differ in intake, although their dose-response curves differed when tested soon after the SS. We also tested whether SS changed the stimulus value of the rat as a social peer; when tested in triads, CTL rats spent similar time in interaction with SS versus CTL rats. In sum, effects of SS on reward sensitivity were greater for males irrespective of administered in adolescence versus adulthood.

Safety on demand: Post-hypnotic suggestions of safety reduce neural signals of reward sensitivity with long-term beneficial effects

Increased reward sensitivity has been proposed as an important transdiagnostic feature for a series of disorders, including addictive behaviors. Earlier studies suggest that a positive affective state characterized by the feeling of safety could reduce an individual's reward sensitivity. A promising technique to establish a feeling of safety on demand is to utilize post-hypnotic suggestions. We hypothesized that the feeling of safety elicited by post-hypnotic suggestions reduces neural signals of reward sensitivity. To test our predictions, we hypnotized 24 highly suggestible participants, suggested them to feel safe and coupled this feeling of safety to a post-hypnotic trigger that reactivates the feeling of safety outside the hypnotic state. Participants then played a risk game both in a safety condition using the post-hypnotic safety trigger and in a control condition using a neutral trigger. Simultaneously, we recorded their EEG. Participants reported significantly higher ratings of safety in the safety condition compared to the control condition. Even several weeks after the main experimental session, the post-hypnotic safety trigger still elicited a significantly stronger feeling of safety compared to the control condition. Moreover, the Reward Positivity (RewP) was significantly reduced in the safety condition. As the RewP amplitude has been proposed as a psychophysiological marker for reward sensitivity, we conclude that the suggestion of safety by post-hypnotic suggestions turns participants into a quiescence motivational state that makes them less reward sensitive. Therefore, we discuss implications of the post-hypnotic safety trigger for the treatment of disorders associated with increased reward sensitivity such as addictive behaviors.

Volume and Connectivity Differences in Brain Networks Associated with Cognitive Constructs of Binge Eating

Bulimia nervosa (BN) and binge eating disorder (BED) are characterized by episodes of eating large amounts of food while experiencing a loss of control. Recent studies suggest that the underlying causes of BN/BED consist of a complex system of environmental cues, atypical processing of food stimuli, altered behavioral responding, and structural/functional brain differences compared with healthy controls (HC). In this narrative review, we provide an integrative account of the brain networks associated with the three cognitive constructs most integral to BN and BED, namely increased reward sensitivity, decreased cognitive control, and altered negative affect and stress responding. We show altered activity in BED/BN within several brain networks, specifically in the striatum, insula, prefrontal cortex (PFC) and orbitofrontal cortex (OFC), and cingulate gyrus. Numerous key nodes in these networks also differ in volume and connectivity compared with HC. We provide suggestions for how this integration may guide future research into these brain networks and cognitive constructs.

How Fuzzy-trace Theory Predicts Development of Risky Decision Making, with Novel Extensions to Culture and Reward Sensitivity

Comprehensive meta-analyses of risky decision making in children, adolescents, and adults have revealed that age trends in disambiguated laboratory tasks confirmed fuzzy-trace theory's prediction that preference for risk decreases monotonically from childhood to adulthood. These findings are contrary to predictions of dual systems or neurobiological imbalance models. Assumptions about increasing developmental reliance on mental representations of the gist of risky options are essential to account for this developmental trend. However, dual systems theory appropriately emphasizes how cultural context changes behavioral manifestation of risk preferences across age and neurobiological imbalance models appropriately emphasize developmental changes in reward sensitivity. All of the major theories include the assumption of increasing behavioral inhibition. Here, we integrate these theoretical constructs-representation, cultural context, reward sensitivity, and behavioral inhibition-to provide a novel framework for understanding and improving risky decision making in youth. We also discuss the roles of critical tests, scientific falsification, disambiguating assessments of psychological and neurological processes, and the misuse of such concepts as ecological validity and reverse inference. We illustrate these concepts by extending fuzzy-trace theory to explain why youth are a major conduit of viral infections, including the virus that causes COVID-19. We conclude by encouraging behavioral scientists to embrace new ways of thinking about risky decision making that go beyond traditional stereotypes about adolescents and that go beyond conceptualizing ideal decision making as trading off degrees of risk and reward.

Heritable variation in locomotion, reward sensitivity and impulsive behaviors in a genetically diverse inbred mouse panel

Drugs of abuse, including alcohol and stimulants like cocaine, produce effects that are subject to individual variability, and genetic variation accounts for at least a portion of those differences. Notably, research in both animal models and human subjects point toward reward sensitivity and impulsivity as being trait characteristics that predict relatively greater positive subjective responses to stimulant drugs. Here we describe use of the eight collaborative cross (CC) founder strains and 38 (reversal learning) or 10 (all other tests) CC strains to examine the heritability of reward sensitivity and impulsivity traits, as well as genetic correlations between these measures and existing addiction-related phenotypes. Strains were all tested for activity in an open field and reward sensitivity (intake of chocolate BOOST®). Mice were then divided into two counterbalanced groups and underwent reversal learning (impulsive action and waiting impulsivity) or delay discounting (impulsive choice). CC and founder mice show significant heritability for impulsive action, impulsive choice, waiting impulsivity, locomotor activity, and reward sensitivity, with each impulsive phenotype determined to be non-correlating, independent traits. This research was conducted within the broader, inter-laboratory effort of the Center for Systems Neurogenetics of Addiction (CSNA) to characterize CC and DO mice for multiple, cocaine abuse related traits. These data will facilitate the discovery of genetic correlations between predictive traits, which will then guide discovery of genes and genetic variants that contribute to addictive behaviors.

Which Child Will Benefit From a Behavioral Intervention for ADHD? A Pilot Study to Predict Intervention Efficacy From Individual Reward Sensitivity

Objective: This article aims to assess whether individual differences in reward sensitivity can be used to predict which children with attention-deficit/hyperactivity disorder (ADHD) will benefit most from behavioral interventions that include reinforcement. Methods: A 12-week behavioral intervention was offered to 21 children with ADHD and their parents. Reward sensitivity was assessed prior to the intervention using a combination of psychological and physiological measures. ADHD symptoms were assessed pre- and posttreatment using the Strengths and Weaknesses of ADHD and Normal behavior (SWAN) rating scale. Results: Lower scores on one of the questionnaire scales were associated with greater pre/posttreatment differences in ADHD symptoms. Conclusion: We found that pre/posttreatment change was associated with one measure of parent-rated reward sensitivity. Children with low impulsive negative behavior toward gaining reward improved most during treatment. This result suggests that aspects of reward-related behaviors in ADHD may be useful to predict the effectiveness of treatment.

Differences in Reward Sensitivity between High and Low Problematic Smartphone Use Adolescents: An ERP Study

Background: Problematic smartphone use is highly prevalent in adolescent populations compared to other age groups (e.g., adults and young children). Previous studies suggested that higher levels of reward sensitivity were associated with problematic smartphone use. Therefore, the current study investigated the neural processing of monetary and social reward and punishment feedbacks between high and low problematic smartphone use adolescents. Methods: 46 adolescents participated in the current study and they were categorized into two groups based on their level of problematic smartphone use: those who obtained low scores on the measure of problematic smartphone use were categorized as Low Problematic Smartphone Use (LPSU), and those who obtained high scores on the measure of problematic smartphone use were categorized as High Problematic Smartphone Use (HPSU). Electrocortical activities were recorded during the processing of monetary and social reward and punishment feedback. Results: (1) LPSUs evoked larger P3 in the social punishment condition than in the monetary punishment condition. HPSUs evoked larger P3 in the social reward condition than in the monetary condition. (2) The feedback-related negativity (FRN) amplitudes in the reward condition were significantly larger than those in the punishment condition. (3) HPSUs induced larger reward positivity in social feedback conditions than in monetary feedback conditions, while there were no significant differences between the two types of conditions in the LPSUs. Discussion: The results provide neural underpinning evidence that high sensitivity to social rewards may be related to problematic smartphone use in adolescence.

Interactions among Reward Sensitivity and Fast-Food Access on Healthy Eating Index Scores in Adolescents: A Cross-Sectional Study

Food cues in the environment may contribute to obesity as the consumption of unhealthy foods may reinforce reward pathways in the brain. To understand how person-level differences in reward sensitivity may be associated with diet quality, this study aimed to examine the moderating role of the availability of fast food in the environment on the relationship between reward sensitivity and diet quality in adolescents. Participants (n = 152; 55% female; Mage: 12.5 ± 0.93 y) completed the drive and reward subscales of the Behavioral Inhibition System (BIS)/Behavioral Activation System (BAS) Scale to assess reward sensitivity and completed two 24 h dietary recalls from which Healthy Eating Index (HEI) scores (total score and subscales of adequacy and moderation) were calculated. Fast-food environment (FFE) was operationalized as the total number of fast-food outlets within 1 km around participants' home address. Linear regressions were used to examine the main effects and interactions between reward sensitivity and FFE in relation to HEI score. Interactions were found between FFE and BAS drive (p = 0.02) and BAS reward (p < 0.01) on HEI adequacy. There were no interaction effects on HEI moderation or HEI total scores. For individuals who had lower access exposure to fast-food outlets (-1 SD), there was a stronger positive association between higher BAS drive (t = 2.85, p = 0.01, 95% CI (0.35, 1.94)) and HEI adequacy scores and between higher BAS reward (t = 3.27, p > 0.01, 95% CI (0.72, 2.93)) and HEI adequacy scores. By examining reward sensitivity to potential food cues in residential neighborhood food environments, it is possible to understand which adolescents are more sensitive to environmental food cues and implement interventions to buffer these influences.

Why Dieters Succeed or Fail: The Relationship Between Reward and Punishment Sensitivity and Restrained Eating and Dieting Success

BACKGROUND

The current study set out to improve our understanding of the characteristics of individuals who are motivated to restrict their food intake yet who nevertheless fail to do so. We examined whether punishment sensitivity (PS) was related to restrained eating, and reward sensitivity (RS) to perceived dieting success. Additionally, it was examined whether executive control (EC) moderates the association between RS and perceived dieting success.

METHODS

Female student participants (N = 290, aged 17-29, BMI between 18.5 and 38.0) completed questionnaires on restrained eating, perceived dieting success, RS and PS, and carried out a behavioral task to index EC.

RESULTS

PS was indeed positively related to restrained eating. RS was positively related to perceived dieting success, yet, EC did not moderate this association.

CONCLUSION

The current study adds to the evidence that PS is related to individuals' motivation to restrict their food intake. Furthermore, it shows support for the suggestion that RS may facilitate food restriction.

Resting-State Theta Oscillations and Reward Sensitivity in Risk Taking

Females demonstrate greater risk aversion than males on a variety of tasks, but the underlying neurobiological basis is still unclear. We studied how theta (4–7 Hz) oscillations at rest related to three different measures of risk taking. Thirty-five participants (15 females) completed the Bomb Risk Elicitation Task (BRET), which allowed us to measure risk taking during an economic game. The Domain-Specific Risk-Taking Scale (DOSPERT) was used to measure self-assessed risk attitudes as well as reward and punishment sensitivities. In addition, the Barratt Impulsiveness Scale (BIS11) was included to quantify impulsiveness. To obtain measures of frontal theta asymmetry and frontal theta power, we used magnetoencephalography (MEG) acquired prior to task completion, while participants were at rest. Frontal theta asymmetry correlated with average risk taking during the game but only in the female sample. By contrast, frontal theta power correlated with risk taking as well as with measures of reward and punishment sensitivity in the joint sample. Importantly, we showed that reward sensitivity mediated a correlation between risk taking and the power of theta oscillations localized to the anterior cingulate cortex. In addition, we observed significant sex differences in source- and sensor-space theta power, risk taking during the game, and reward sensitivity. Our findings suggest that sensitivity to rewards, associated with resting-state theta oscillations in the anterior cingulate cortex, is a trait that potentially contributes to sex differences in risk taking.

Reward sensitivity and action in Parkinson's disease patients with and without apathy

Clinical apathy results in dysfunction of goal directed behaviour, a key component of which is the initiation of action. Previous work has suggested that blunting of reward sensitivity is an important mechanism underlying apathy. However, an additional component might be impoverished initiation of action itself. This study aims to investigate the link between motivation and motor output and its association with apathy and dopamine. An oculomotor task that measures pupillary and saccadic response to monetary incentives was used to assess reward sensitivity, first in 23 young and 18 elderly controls, and then in 22 patients with Parkinson's disease tested ON and OFF dopaminergic medication. To distinguish between pupillary responses to anticipated reward alone versus responses associated with motor preparation, a saccadic 'go/no-go' task was performed. Half of the trials required a saccade to be initiated to receive a reward and in the remaining trials no action was required but reward was still obtained. No significant difference in pupil response was demonstrated between the two conditions in all groups tested, suggesting pupillary responses to rewards are not contingent upon motor preparation in Parkinson's disease. Being ON or OFF dopamine did not influence this response either. Previous work demonstrated associations between apathy and pupillary reward insensitivity in Parkinson's disease. Here we observed this effect only when an action was required to receive a reward, and only in the ON state. These findings suggest that apathy in Parkinson's disease is linked to reduced reward sensitivity and that this is most prominently observed when actions have to be initiated to rewarding goals, with the effect modulated by being ON dopaminergic medication. OFF medication, there was no such strong relationship, and similarly in the 'no-go' conditions, either ON or OFF dopaminergic drugs. The results provide preliminary data which suggest that apathy in Parkinson's disease is associated with a reduction in reward sensitivity and this is most evident when associated with initiation of goal directed actions in the presence of adequate dopamine.

Expectancy to Eat Modulates Cognitive Control and Attention Toward Irrelevant Food and Non-food Images in Healthy Starving Individuals. A Behavioral Study

It is thought that just as hunger itself, the expectancy to eat impacts attention and cognitive control toward food stimuli, but this theory has not been extensively explored at a behavioral level. In order to study the effect of expectancy to eat on attentional and cognitive control mechanisms, 63 healthy fasting participants were presented with an affective priming spatial compatibility Simon task that included both food and object (non-food) distracters. The participants (N = 63) were randomly assigned to two groups: an "immediate expectancy" group made up of participants who expected to eat immediately after the task (N = 31; females = 21; age = 26.8 ± 9.6) and a "delayed expectancy" cohort made up of individuals who expected to eat a few hours later (N = 32; females = 21; age = 25.0 ± 8.0). Slower reaction times (RTs) toward the food and non-food distracters and a more pronounced effect on the RTs in the incompatible condition [i.e., the Simon effect (SE)] were noted in both groups. The effect of the food and non-food distracters on the RTs was more pronounced in the immediate with respect to the delayed expectancy group. The magnitude of the SE for the food and the non-food distracters was also greater in the immediate with respect to the delayed expectancy group. These results seem to indicate that when the expectancy to eat is short, the RTs are delayed, and the SE is more pronounced when food and non-food distracters are presented. Instead, when the expectancy to eat is more distant, the distracters have less of an effect on the RTs and the correspondence effect is smaller. Our results suggest that the expectancy to eat can modulate both attention orienting and cognitive control mechanisms in healthy fasting individuals when distracting details are competing with information processing during goal directed behavior.

The Association between Reward Sensitivity and Activity Engagement: the Influence of Delay Discounting and Anhedonia

Aim

Reward sensitivity affects individuals’ motivation to engage in goal-directed behavior. Other concepts, critical for reward appraisal, that potentially influence activity participation encompass delay discounting and anhedonia. The aim of this study was to test the hypothesis that anhedonia and delay discounting influence the relationship between reward sensitivity and activity engagement.

Methods

In total, 37 inpatient patients with an alcohol use disorder (AUD) and 37 matched healthy controls completed the behavioral activation system scale (BAS scale), the Pleasant Activities List (PAL), the Snaith–Hamilton Pleasure Scale (SHAPS) and the Delay Discounting Task (DDT).

Results

Patients differed from controls on SHAPS, DDT-k, PAL substance-related activities (SRA), but not BAS and PAL non-substance-related activities (non-SRA). Correlational analyses revealed a strong correlation between BAS and PAL non-SRA in both patients (r = 0.53) and controls (r = 0.47), but also with PAL-SRA in patients (r = 0.40), although not controls (r = 0.09). BAS was negatively correlated with SHAPS in both groups and with DDT in controls. SHAPS was negatively linked to PAL non-SRA in both groups. The BAS-PAL non-SRA relationship was influenced by discount rates in controls.

Conclusion

A strong link exists between reward sensitivity and engagement in non-SRA in both groups. Delay discounting affects the reward sensitivity and non-SRA association in healthy controls, while anhedonia did not impact the association between reward sensitivity and engagement in (non-)SRA in both conditions.

The Role of Social Reward and Corticostriatal Connectivity in Substance Use

This report describes an ongoing R03 grant that explores the links between trait reward sensitivity, substance use, and neural responses to social and nonsocial reward. Although previous research has shown that trait reward sensitivity and neural responses to reward are linked to substance use, whether this relationship is impacted by how people process social stimuli remains unclear. We are investigating these questions via a neuroimaging study with college-aged participants, using individual difference measures that examine the relation between substance use, social context, and trait reward sensitivity with tasks that measure reward anticipation, strategic behavior, social reward consumption, and the influence of social context on reward processing. We predict that substance use will be tied to distinct patterns of striatal dysfunction. Specifically, reward hyposensitive individuals will exhibit blunted striatal responses to social and non-social reward and enhanced connectivity with the orbitofrontal cortex; in contrast, reward hypersensitive individuals will exhibit enhanced striatal responses to social and non-social reward and blunted connectivity with the orbitofrontal cortex. We also will examine the relation between self-reported reward sensitivity, substance use, and striatal responses to social reward and social context. We predict that individuals reporting the highest levels of substance use will show exaggerated striatal responses to social reward and social context, independent of self-reported reward sensitivity. Examining corticostriatal responses to reward processing will help characterize the relation between reward sensitivity, social context and substance use while providing a foundation for understanding risk factors and isolating neurocognitive mechanisms that may be targeted to increase the efficacy of interventions.

The Effects of a 12-Month Weight Loss Intervention on Cognitive Outcomes in Adults with Overweight and Obesity

Obesity is associated with poorer executive functioning and reward sensitivity. Yet, we know very little about whether weight loss through diet and/or increased exercise engagement improves cognitive function. This study evaluated whether weight loss following a dietary and exercise intervention was associated with improved cognitive performance. We enrolled 125 middle-aged adults with overweight and obesity (98 female) into a 12-month behavioral weight loss intervention. Participants were assigned to one of three groups: energy-restricted diet alone, an energy-restricted diet plus 150 min of moderate intensity exercise per week or an energy restricted diet plus 250 min of exercise per week. All participants completed tests measuring executive functioning and/or reward sensitivity, including the Iowa Gambling Task (IGT). Following the intervention, weight significantly decreased in all groups. A MANCOVA controlling for age, sex and race revealed a significant multivariate effect of group on cognitive changes. Post-hoc ANCOVAs revealed a Group × Time interaction only on IGT reward sensitivity, such that the high exercise group improved their performance relative to the other two intervention groups. Post-hoc ANCOVAs also revealed a main effect of Time, independent of intervention group, on IGT net payoff score. Changes in weight were not associated with other changes in cognitive performance. Engaging in a high amount of exercise improved reward sensitivity above and beyond weight loss alone. This suggests that there is additional benefit to adding exercise into behavioral weight loss regimens on executive functioning, even without additional benefit to weight loss.

Reinforcement-Sensitive Personality Traits Associated With Passion in Heterosexual Intimate Relationships: An fNIRS Investigation

According to the triangular theory of love, passion is an indispensable component of romantic love. Some brain imaging studies have shown that passionate arousal in intimate relationships is associated with the reward circuits in the brain. We hypothesized that the individual reward sensitivity trait is also related to passion in intimate relationships, and two separate studies were conducted in the present research. In the first study, 558 college students who were currently in love were selected as participants. The correlation between intimacy and reinforcement sensitivity in individuals identifying as heterosexual was explored using the Sensitivity to Punishment and Sensitivity to Reward Questionnaire, the Passionate Love Scale, and the Triangular Love Scale. In the second study, participants were 42 college students who were also currently in love. Functional near-infrared spectroscopy (fNIRS) was adopted to explore the neurophysiological interaction between reward sensitivity and emotional arousal induced in participants when presented a photograph of their partner, a friend, or a stranger. The results showed that reward sensitivity was positively correlated with passion, and punishment sensitivity was negatively correlated with intimacy and commitment. Significant interactions between reward sensitivity and photograph type were found, and the triangular part of the inferior frontal gyrus showed a particular relevance to the reward-sensitive personality trait toward partners. Overall, the findings support reinforcement sensitivity theory and suggest that reinforcement-sensitive personality traits (personality traits of reward and punishment sensitivity) are associated with all three components of love, with only reward sensitivity being related to passion.

Dopamine and reward hypersensitivity in Parkinson's disease with impulse control disorder

Impulse control disorders in Parkinson's disease are common neuropsychiatric complications associated with dopamine replacement therapy. Some patients treated with dopamine agonists develop pathological behaviours, such as gambling, compulsive eating, shopping, or disinhibited sexual behaviours, which can have a severe impact on their lives and that of their families. In this study we investigated whether hypersensitivity to reward might contribute to these pathological behaviours and how this is influenced by dopaminergic medication. We asked participants to shift their gaze to a visual target as quickly as possible, in order to obtain reward. Critically, the reward incentive on offer varied over trials. Motivational effects were indexed by pupillometry and saccadic velocity, and patients were tested ON and OFF dopaminergic medication, allowing us to measure the effect of dopaminergic medication changes on reward sensitivity. Twenty-three Parkinson's disease patients with a history of impulse control disorders were compared to 26 patients without such behaviours, and 31 elderly healthy controls. Intriguingly, behavioural apathy was reported alongside impulsivity in the majority of patients with impulse control disorders. Individuals with impulse control disorders also exhibited heightened sensitivity to exogenous monetary rewards cues both ON and OFF (overnight withdrawal) dopamine medication, as indexed by pupillary dilation in anticipation of reward. Being OFF dopaminergic medication overnight did not modulate pupillary reward sensitivity in impulse control disorder patients, whereas in control patients reward sensitivity was significantly reduced when OFF dopamine. These effects were independent of cognitive impairment or total levodopa equivalent dose. Although dopamine agonist dose did modulate pupillary responses to reward, the pattern of results was replicated even when patients with impulse control disorders on dopamine agonists were excluded from the analysis. The findings suggest that hypersensitivity to rewards might be a contributing factor to the development of impulse control disorders in Parkinson's disease. However, there was no difference in reward sensitivity between patient groups when ON dopamine medication, suggesting that impulse control disorders may not emerge simply because of a direct effect of dopaminergic drug level on reward sensitivity. The pupillary reward sensitivity measure described here provides a means to differentiate, using a physiological measure, Parkinson's disease patients with impulse control disorder from those who do not experience such symptoms. Moreover, follow-up of control patients indicated that increased pupillary modulation by reward can be predictive of the risk of future emergence of impulse control disorders and may thereby provide the potential for early identification of patients who are more likely to develop these symptoms.

Does the Punishment Fit the Crime (and Immune System)? A Potential Role for the Immune System in Regulating Punishment Sensitivity

Although the criminal justice system is designed around the idea that individuals are invariant in their responses to punishment, research indicates that individuals exhibit a tremendous amount of variability in their punishment sensitivity. This raises the question of why; what are the individual- and situation-level variables that impact a person’s sensitivity to punishment? In the current research, we synthesize theory and research on inflammation, learning, and evolutionary biology to examine the relationship between inflammatory activity and sensitivity to punishment. These theories combine to predict that inflammatory activity – which is metabolically costly and reflects a context in which the net payoff associated with future oriented behaviors is diminished – will decrease sensitivity to punishment, but not rewards. Consistent with this hypothesis, Study 1 found that in U.S. states with a higher infectious disease burden (a proxy for average levels of inflammatory activity) exhibit harsher sentencing in their criminal justice systems. Studies 2 and 3 experimentally manipulated variables known to impact bodily inflammatory activity and measured subsequent punishment and reward sensitivity using a probabilistic selection task. Results revealed that (a) increasing inflammation (i.e., completing the study in a dirty vs. clean room) diminished punishment sensitivity (Study 2), whereby (b) administering a non-steroidal anti-inflammatory drug, suppressing inflammatory activity, enhanced it. No such changes were found for reward sensitivity. Together, these results provide evidence of a link between the activities of the immune system and punishment sensitivity, which may have implications for criminal justice outcomes.

Stressful life events moderate the effect of neural reward responsiveness in childhood on depressive symptoms in adolescence

BACKGROUND

Reward processing deficits have been implicated in the etiology of depression. A blunted reward positivity (RewP), an event-related potential elicited by feedback to monetary gain relative to loss, predicts new onsets and increases in depression symptoms. Etiological models of depression also highlight stressful life events. However, no studies have examined whether stressful life events moderate the effect of the RewP on subsequent depression symptoms. We examined this question during the key developmental transition from childhood to adolescence.

METHODS

A community sample of 369 children (mean age of 9) completed a self-report measure of depression symptoms. The RewP to winning v. losing was elicited using a monetary reward task. Three years later, we assessed stressful life events occurring in the year prior to the follow-up. Youth depressive symptoms were rated by the children and their parents at baseline and follow-up.

RESULTS

Stressful life events moderated the effect of the RewP on depression symptoms at follow-up such that a blunted RewP predicted higher depression symptoms in individuals with higher levels of stressful life events. This effect was also evident when events that were independent of the youth's behavior were examined separately.

CONCLUSIONS

These results suggest that the RewP reflects a vulnerability for depression that is activated by stress.

Altered core networks of brain connectivity and personality traits in internet gaming disorder

BACKGROUND AND AIMS

Although the Internet has provided convenience and efficiency in many areas of everyday life, problems stemming from Internet use have also been identified, such as Internet gaming disorder (IGD). Internet addiction, which includes IGD, can be viewed as a behavioral addiction or impulse control disorder. This study investigated the altered functional and effective connectivity of the core brain networks in individuals with IGD compared to healthy controls (HCs).

METHODS

Forty-five adults with IGD and 45 HCs were included in this study. To examine the brain networks related to personality traits that influence problematic online gaming, the left and right central executive network (CEN) and the salience network (SN) were included in the analysis. Also, to examine changes in major brain network topographies, we analyzed the default mode network (DMN).

RESULTS

IGD participants showed lower functional connectivity between the dorsal lateral prefrontal cortex (DLPFC) and other regions in the CEN than HC participants during resting state. Also, IGD participants revealed reduced functional connectivity between the dorsal anterior cingulate cortex and other regions in the SN and lower functional connectivity in the medial prefrontal cortex of the anterior DMN. Notably, in IGD individuals but not HC individuals, there was a positive correlation between IGD severity and effective connectivity and a positive correlation between reward sensitivity and effective connectivity within the ventral striatum of the SN.

CONCLUSIONS

Problematic online gaming was associated with neurofunctional alterations, impairing the capacity of core brain networks.

A model of reinforcement sensitivity, impulsivity, alcohol use, and risky sexual behavior in a sample of young adult drinkers

This study tested a structural equation model linking reinforcement sensitivity to subsequent emotion-based impulsivity (i.e., positive and negative urgency), alcohol use, and risky sexual behavior among a sample of 753 undergraduate drinkers. A hypothesized Sensitivity to Punishment (SP) × Sensitivity to Reward (SR) interaction significantly predicted both positive and negative urgency. At low levels of SR, SP had a significant negative effect on positive urgency and a significant positive effect on negative urgency. However, at high levels of SR, SP had significant positive effects on both types of urgency. Results indicated that positive and negative urgency mediate the associations between reinforcement sensitivity and both alcohol use and risky sexual behavior. Moreover, results demonstrated that at low levels of SR, SP is indirectly associated with decreased alcohol use. However, as SR increases, SP is indirectly associated with increased alcohol use and risky sexual behavior, due to the joint effect of high SP and SR on emotion-based impulsivity. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Individual Differences in Hippocampal Volume as a Function of BMI and Reward Sensitivity

Sensitivity to reward is a personality trait that predisposes a person to several addictive behaviors, including the presence of different risky behaviors that facilitates uncontrolled eating. However, the multifactorial nature of obesity blurs a direct relationship between the two factors. Here, we studied the brain anatomic correlates of the interaction between reward sensitivity and body mass index (BMI) to investigate whether the coexistence of high BMI and high reward sensitivity structurally alters brain areas specifically involved in the regulation of eating behavior. To achieve this aim, we acquired T1-weighted images and measured reward sensitivity using the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ) and BMI in a sample of 206 adults. Results showed that reward sensitivity and BMI were not significantly correlated. However, neuroimaging results confirmed a relationship between BMI and reduced volume in the medial and lateral orbitofrontal cortex, and between reward sensitivity and lower striatum volume. Importantly, the interaction between the two factors was significantly related to the right anterior hippocampus volume, showing that stronger reward sensitivity plus a higher BMI were associated with reduced hippocampal volume. The hippocampus is a brain structure involved in the higher-order regulation of feeding behavior. Thus, a dysfunctional hippocampus may contribute to maintaining a vicious cycle that predisposes people to obesity.

Investigating the relationship between reward sensitivity, impulsivity, and food addiction: A systematic review

OBJECTIVE

The aim of the current research was to identify the extent to which reward sensitivity and impulsivity were related to food addiction.

METHOD

Forty-five studies, published from 2009 to June 2019, investigating reward sensitivity and/or impulsivity with food addiction as measured by the Yale Food Addiction Scale were reviewed.

RESULTS

Reward sensitivity, as measured by the Sensitivity to Reward (SR) scale, was positively associated with food addiction in two studies, but failed to yield consistent results in other studies when measured with the Behavioral Inhibition/Behavioral Activation Scales. Self-report impulsivity, as measured by the Barratt Impulsiveness Scale (BIS-11), was consistently associated with food addiction, with attentional impulsivity and motor impulsivity the most consistent subscales. Similarly, food addiction was also consistently associated with Negative Urgency, Positive Urgency, and Lack of Perseverance as measured by the UPPS-P Impulsive Behavior Scale. Food addiction was inconsistently associated with disinhibition, as measured by behavioral tasks, indicating food addiction appears more aligned with self-report measures of impulsivity.

CONCLUSIONS

Research in this field is dominated by university student, overweight and obese samples. Additional research is required to further tease out these relationships.

Can Parenting Practices Moderate the Relationship between Reward Sensitivity and Adolescents' Consumption of Snacks and Sugar-Sweetened Beverages?

Background: Reward sensitivity has been associated with adolescents’ intake of unhealthy snacks and sugar-sweetened beverages. However, so far, there are no studies published describing the impact of parenting practices on this relationship. The present study will, therefore, investigate whether food parenting practices can moderate the association between reward sensitivity and diet intakes. Method: A cross-sectional research study was conducted among 14- to 16-year old Flemish adolescents (n = 867, age 14.7 ± 0.8 y, 48.1% boys) and a subset of their parents (n = 131), collecting data on daily intakes, reward sensitivity, and food parenting practices. Linear regression was used to assess the moderation effect of parenting practices (both adolescent- and parent-reported) on the relationship between reward sensitivity, and diet using SPSS 25.0. Results: In the main analysis (adolescent-reported), no significant moderation effects were found for parenting practices on the relationship between reward sensitivity and diet. However, the sensitivity analysis (parent-reported) showed a moderation effect for health-reducing parenting practices on the association between reward sensitivity and unhealthy snack intake (β = 0.297, 95% CI = 0.062, 0.531, p = 0.01). Conclusion: Given the difference in the effect of parenting practices between the adolescent- and parent-reported data, our inconclusive findings warrant more research in larger adolescent-parent dyad samples.

No Differential Reward Responsivity and Drive, Punishment Sensitivity or Attention for Cues Signaling Reward or Punishment in Adolescents With Obesity

Although it has been proposed that obese and healthy weight individuals might differ in their reward and punishment sensitivity, the literature shows diverse and inconsistent findings. The current study was set out to examine the role of reward and punishment sensitivity in adolescent obesity by differentiating between reward responsivity and reward drive, and by complementing self-report measures with performance-based measures indexing attention for cues signaling reward and punishment as well as effort to approach reward and avoid punishment. Participants were adolescents aged 12-23, with obesity (n = 51, adjusted BMI [(actual BMI/Percentile 50 of BMI for age and gender) × 100) between 143 and 313%], and with a healthy weight (n = 51, adjusted BMI between 75 and 129%). Individuals with obesity did not significantly differ from adolescents with a healthy weight in reward responsivity, reward drive or attention to cues signaling reward. Further, no differences in self-reported punishment sensitivity or attention for cues signaling punishment were found between obese and healthy weight adolescents. The current study thus does not corroborate the theories that general reward and punishment sensitivity play a role in obesity.

Food Addiction: Implications for the Diagnosis and Treatment of Overeating

With the obesity epidemic being largely attributed to overeating, much research has been aimed at understanding the psychological causes of overeating and using this knowledge to develop targeted interventions. Here, we review this literature under a model of food addiction and present evidence according to the fifth edition of the Diagnostic and Statistical Manual (DSM-5) criteria for substance use disorders. We review several innovative treatments related to a food addiction model ranging from cognitive intervention tasks to neuromodulation techniques. We conclude that there is evidence to suggest that, for some individuals, food can induce addictive-type behaviours similar to those seen with other addictive substances. However, with several DSM-5 criteria having limited application to overeating, the term ‘food addiction’ is likely to apply only in a minority of cases. Nevertheless, research investigating the underlying psychological causes of overeating within the context of food addiction has led to some novel and potentially effective interventions. Understanding the similarities and differences between the addictive characteristics of food and illicit substances should prove fruitful in further developing these interventions.

Delay discounting and reward sensitivity in a 2 × 2 study of bipolar disorder and alcohol dependence

BACKGROUND AND AIMS

Separate studies have shown increased delay discounting in people with bipolar disorder (BD) and people with alcohol dependence (AD) relative to people without mental health problems. Delay discounting was compared in people with no mental health problems, AD, BD and AD plus BD. Associations of delay discounting with self-reported impulsivity and reward sensitivity were also assessed.

DESIGN

The study was a two-by-two factorial comparative observational design.

SETTING

Data were collected at baseline diagnostic visits as part of a neuroimaging study at a medical university in South Carolina, USA.

PARTICIPANTS

Twenty-two BD + AD, 33 BD, 28 AD and 27 people without mental health problems participated.

MEASUREMENTS

Diagnostic and clinician-rated symptom measures, self-report questionnaires and a computerized delay discounting task were administered. Two-by-two general linear univariate models were tested to examine between-group differences on discounting rates, and bivariate correlations and hierarchical regression analyses were performed to examine associations between discounting rates and self-reported reward sensitivity and impulsivity.

FINDINGS

There was a significant main effect of AD (P = 0.006, η2  = 0.068). The main effect of BD and the BD × AD interaction terms were non-significant (P ≥ 0.293, η2  ≤ 0.010). Reward sensitivity and impulsivity were not significantly associated with discounting rates after adjustment for the other (P ≥ 0.089).

CONCLUSIONS

People with alcohol dependence appear to have higher delay discounting, while previously found associations between bipolar disorder and delay discounting may be secondary to alcohol use disorder.

Testing a model of reward sensitivity, implicit and explicit drinker identity and hazardous drinking

Objective: The aim of this study was to investigate both implicit and explicit drinker identity as mediators of reward sensitivity and problematic drinking. University students engage in problematic levels of alcohol consumption, exposing them to increased negative health outcomes. Although personality traits (e.g. reward sensitivity) and social-cognitive variables (e.g. implicit and explicit drinker identity) have been used to investigate drinking behaviour, few studies link personality and multiple indices of drinker identity to problematic drinking. Design: University students (N = 136) completed a drinker identity implicit association test, and questionnaires measuring reward sensitivity, explicit binge drinker identity and problematic drinking as part of a lab-based correlational study. Main Outcome Measures: The Alcohol Use Disorders Identification Test was the main outcome measure with participants self-reporting drinking frequency, quantity and negative physical and psychological outcomes of drinking over the past 3-months. Results: A mediation model revealed that reward sensitivity was significantly associated with explicit, but not implicit, binge drinker identity. Explicit binge drinker identity mediated the reward sensitivity and problematic drinking association. Conclusion: This research provides an evidence base for identity-based drinking interventions for students characterised by high reward sensitivity, by promoting identities that do not idealise problematic drinking behaviour.

Retrospective and prospective assessments of gambling-related behaviors across the female menstrual cycle

BACKGROUND AND AIMS

Despite increases in female gambling, little research investigates female-specific factors affecting gambling behavior (GB). Although research suggests that some addictive behaviors may fluctuate across menstrual cycle phase (MCP), gambling requires further investigation. In two studies, we examined associations between MCP and three risky GBs: time spent gambling, money spent gambling, and the probability of consuming alcohol while gambling. Associations between MCP and negative affect were also examined in Study 2. We predicted that, consistent with self-medication theory, increases in negative affect (Study 2) and risky GBs (Studies 1 and 2) would occur premenstrually/menstrually relative to other phases.

METHODS

Data were obtained from 33 female gamblers using a retrospective timeline followback procedure (Study 1) and from 20 female gamblers using a prospective 32-day, daily diary method (Study 2). In Study 2, salivary progesterone levels verified self-reported MCP validity.

RESULTS

Findings revealed significant, but somewhat inconsistent, MCP effects on GBs across studies. The self-medication hypothesis was partially supported. Increases relative to another MCP(s) were found for alcohol consumption while gambling premenstrually, time spent gambling menstrually/premenstrually, money spent gambling menstrually, and negative affect premenstrually. Unexpectedly, findings more consistently indicated that GBs increased during ovulation, suggestive of enhanced reward sensitivity. Progesterone assays validated self-reported MCP (Study 2).

DISCUSSION AND CONCLUSIONS

The results suggest a role of ovarian hormones on negative affect and GBs in females. This research could lead to the identification of female-specific factors affecting gambling and the development of more effective interventions for females with, or at risk for, problematic gambling.

Uncontrolled eating: a unifying heritable trait linked with obesity, overeating, personality and the brain

Many eating-related psychological constructs have been proposed to explain obesity and overeating. However, these constructs, including food addiction, disinhibition, hedonic hunger, emotional eating, binge eating and the like all have similar definitions, emphasizing loss of control over intake. As questionnaires measuring the constructs correlate strongly (r > 0.5) with each other, we propose that these constructs should be reconsidered to be part of a single broad phenotype: uncontrolled eating. Such an approach enables reviewing and meta-analysing evidence obtained with each individual questionnaire. Here, we describe robust associations between uncontrolled eating, body mass index (BMI), food intake, personality traits and brain systems. Reviewing cross-sectional and longitudinal data, we show that uncontrolled eating is phenotypically and genetically intertwined with BMI and food intake. We also review evidence on how three psychological constructs are linked with uncontrolled eating: lower cognitive control, higher negative affect and a curvilinear association with reward sensitivity. Uncontrolled eating mediates all three constructs' associations with BMI and food intake. Finally, we review and meta-analyse brain systems possibly subserving uncontrolled eating: namely, (i) the dopamine mesolimbic circuit associated with reward sensitivity, (ii) frontal cognitive networks sustaining dietary self-control and (iii) the hypothalamus-pituitary-adrenal axis, amygdala and hippocampus supporting stress reactivity. While there are limits to the explanatory and predictive power of the uncontrolled eating phenotype, we conclude that treating different eating-related constructs as a single concept, uncontrolled eating, enables drawing robust conclusions on the relationship between food intake and BMI, psychological variables and brain structure and function.

Nonacute effects of cannabis use on motivation and reward sensitivity in humans: A systematic review

Reduced motivation is often noted as a consequence of cannabis use. However, prior studies examining this association have suboptimally operationalized motivation and have yielded mixed findings. This review discusses motivation and the closely related construct of reward sensitivity. We summarize the available literature examining associations between motivation and cannabis use, addressing the following questions: (a) Is there evidence for decreased motivation among cannabis users? (b) Is there evidence that lack of motivation among cannabis users is specific to their use of cannabis (rather than to use of other addictive drugs)? and (c) Is there evidence suggesting a causal relationship between cannabis use and motivation? Using PubMed, PsycINFO, and WebofScience, we conducted a literature search of studies examining nonacute effects of cannabis use on motivation, apathy, amotivation, effort, and reward sensitivity in humans. This search yielded 22 studies, which were reviewed in detail. We conclude that, although cross-sectional evidence of a cannabis-specific effect on motivation is equivocal, there is partial support from longitudinal studies for a causal link between cannabis use and reduced motivation. Additionally, we propose that reward sensitivity and motivation represent distinct yet related constructs and that reductions in one may not always lead to reductions in the other. Future work should longitudinally examine associations between cannabis use, motivation, and reward sensitivity; carefully define and operationalize these constructs; and control for the influence of potential confounding factors. (PsycINFO Database Record

Introjective Individuals Tend Toward Anhedonia: Self-Report and Experimental Evidence

A broad line of research has conceptualized personality based on the interaction of two aspects: interpersonal relatedness and self-definition. This theoretical corpus understands these functions as two poles according to the patterns of interaction and relevance in personality. Additionally, the exacerbation of one of these poles generates a psychopathological model that identifies three types of depressive experience: anaclitic, introjective, or mixed pattern. Understanding the lack of interest as a key symptom of depression, this experiment evaluates a relation for anhedonia and the polarities model configuration using an empirical and experimental protocol. We tested 177 individuals using the Beck Depression Inventory (BDI) subscale for anhedonia and a visual discrimination task with a specific reward system, which was implemented to study reinforcement sensitivity. Participants were classified into four groups by the polarities of experience model. The subscale's results showed that individuals with an introjective character exhibited an enhanced anhedonic symptomatology but no co-occurrence of this evidence on the experimental protocol. These results empirically support the two polarities of the depressive personality model and raise new questions regarding how to experimentally test this relation.