Contributions of Reward Sensitivity to Ventral Striatum Activity Across Adolescence and Early Adulthood

Sample size estimation for task-related functional MRI studies using Bayesian updating

Task-related functional MRI (fMRI) studies need to be properly powered with an adequate sample size to reliably detect effects of interest. But for most fMRI studies, it is not straightforward to determine a proper sample size using power calculations based on published effect sizes. Here, we present an alternative approach of sample size estimation with empirical Bayesian updating. First, this method provides an estimate of the required sample size using existing data from a similar task and similar region of interest. Using this estimate researchers can plan their research project, and report empirically determined sample size estimations in their research proposal or pre-registration. Second, researchers can expand the sample size estimations with new data. We illustrate this approach using four existing fMRI data sets where Cohen's d is the effect size of interest for the hemodynamic response in the task condition of interest versus a control condition, and where a Pearson correlation between task effect and age is the covariate of interest. We show that sample sizes to reliably detect effects differ between various tasks and regions of interest. We provide an R package to allow researchers to use Bayesian updating with other task-related fMRI studies.

Prospective association between screen use modalities and substance use experimentation in early adolescents

BACKGROUND

There are limited large-scale, prospective analyses examining contemporary screen use and substance use experimentation in early adolescents. The current study aimed to determine associations between eight forms of contemporary screen modalities and substance use experimentation one year later in a national cohort of 11-12-year-olds in the United States.

METHODS

The sample consisted of 8006 early adolescents (47.9 % female and 41.6 % racial/ethnic minority) from the prospective cohort data of the Adolescent Brain Cognitive Development (ABCD) Study. Logistic regression analyses were conducted to evaluate the prospective associations between screen time (eight different types and total) in Year 2 and substance use experimentation (alcohol, nicotine, cannabis, any substance use) in Year 3, adjusting for covariates and Year 2 substance use experimentation.

RESULTS

Total screen time was prospectively associated with alcohol, nicotine, and cannabis experimentation. Each additional hour spent on social media (AOR 1.20; 95 % CI 1.14-1.26), texting (AOR 1.18; 95 % CI 1.12-1.24), and video chatting (AOR 1.09; 95 % CI 1.03-1.16) was associated with higher odds of any substance experimentation. Social media use and texting were also associated with higher odds of alcohol, cannabis, and nicotine experimentation; however, television/movies, videos, video games, and the internet were not. Moreover, video chatting was associated with higher odds of cannabis and nicotine experimentation.

CONCLUSIONS

Our findings indicate that digital social connections, such as via social media, texting, and video chatting, are the contemporary screen modalities that are associated with early adolescent substance experimentation. Future research could explore the mechanisms underlying these associations to inform intervention strategies.

Development of Self-Concept in Childhood and Adolescence: How Neuroscience Can Inform Theory and Vice Versa

How do we develop a stable and coherent self-concept in contemporary times? Susan Harter's original work, The Construction of Self (1999; 2012), argues that cognitive and social processes are building blocks for developing a coherent sense of self, resulting in self-concept clarity across various domains in life (e.g., [pro-]social, academic, and physical). Here, we show how this framework guides and can benefit from recent findings on (1) the prolonged and nonlinear structural brain development during childhood and adolescence, (2) insights from developmental neuroimaging studies using self-concept appraisal paradigms, (3) genetic and environmental influences on behavioral and neural correlates of self-concept development, and (4) youth's perspectives on self-concept development in the context of 21st century global challenges. We examine how neuroscience can inform theory by testing several compelling questions related to stability versus change of neural, behavioral, and self-report measures and we reflect on the meaning of variability and change/growth.

Development of Self-Reported Reward Responsiveness and Inhibitory Control and the Role of Clinical and Neural Predictors

OBJECTIVE

Understanding the development of adolescent reward responsiveness and inhibitory control is important as they are implicated in key outcomes, such as depression. However, relatively few studies have examined the self-reported experience of this development longitudinally, and past findings have been mixed. Here, we examined the longitudinal development of self-reported reward responsiveness and inhibitory control in youth, as well as clinical and neural measures as predictors of these longitudinal trajectories.

METHOD

We assessed 223 youth aged 9-17 across 36 months. We modeled growth trajectories of several measures of reward responsiveness and inhibitory control using multilevel models. We tested reward-related functional connectivity, depression symptoms, and parental risk for psychopathology as moderators of longitudinal growth.

RESULTS

Self-reported inhibitory control increased linearly across adolescence. However, contrary to hypotheses and common models of adolescent development, self-reported reward responsiveness decreased linearly across adolescence. Baseline functional connectivity and clinical risk measures did not significantly moderate trajectories.

CONCLUSION

Results suggest that within-person changes in the phenomenological experience of reward responsiveness may not match developmental expectations based on cross-sectional and neuroimaging studies. More attention is needed to the longitudinal study of subjective experience of reward responsiveness.

Distinct Topological Properties of the Reward Anticipation Network in Preadolescent Children With Binge Eating Disorder Symptoms

OBJECTIVE

Few studies have considered the neural underpinnings of binge eating disorder (BED) in children, despite clinical and subclinical symptom presentation occurring in this age group. Symptom presentation at this age is of clinical relevance, as early onset of binge eating is linked to negative health outcomes. Studies in adults have highlighted dysfunction in the frontostriatal reward system as a potential candidate for binge eating pathophysiology, although the exact nature of such dysfunction is currently unclear.

METHOD

Data from 83 children (mean age 9.9 years, SD = 0.60) with symptoms of BED (57% girls) and 123 control participants (mean age 10.0 years, SD = 0.60) (52% girls) were acquired from the 4.0 baseline release of the Adolescent Brain Cognitive Development Study. Task-based graph theoretic techniques were used to analyze data from anticipation trials of the monetary incentive delay task. Network and nodal properties were compared between groups.

RESULTS

The BED-S group showed alterations in topological properties associated with the frontostriatal subnetwork, such as reduced nodal efficiency in the superior frontal gyrus, nucleus accumbens, putamen, and in normal sex-difference patterns of these properties, such as diminished girls-greater-than-boys pattern of betweenness-centrality in nucleus accumbens observed in controls.

CONCLUSION

Distinct network properties and sex-difference patterns in preadolescent children with BED-S suggest dysregulation in the reward system compared to those of matched controls. For the first time, these results quantify this dysregulation in terms of systems-level properties during anticipation of monetary reward and significantly inform the early and sex-related brain markers of BED symptoms.

PLAIN LANGUAGE SUMMARY

Binge eating disorder is the most common eating disorder. One factor that may contribute to binge eating is dysregulation of the reward system in the brain. This study analyzed brain activity during anticipation of monetary rewards in 83 youth with and 123 children without binge eating disorder symptoms from the Adolescent Brain Cognitive Development Study. The authors found specific alterations in the frontostriatal system, responsible for reward processing, in children with binge eating disorder symptoms, compared to the control group, suggesting dysregulation of the reward system.

Revisiting the musical reminiscence bump: insights from neurocognitive and social brain development in adolescence

Music listening is enjoyed across the lifespan and around the world. This has spurred many theories on the evolutionary purpose of music. The Music for Social Bonding hypothesis posits that the human capacity to make music evolved for the purpose of creating and preserving relationships between one another. Considering different time periods of music use across the lifespan, adolescence is especially a period of social reorientation away from family towards peers, characterized by new social bonds and increased prosocial behavior. This shift is accompanied by notable structural and functional changes in brain networks supporting reward processing and prosocial behavior. Reviewing the extant literature on developmental cognitive neuroscience and adolescent music use, we propose that neurocognitive changes in the reward system make adolescence an ideal developmental time window for investigating interactions between prosocial behavior and reward processing, as adolescence constitutes a time of relative increase in music reward valuation. Testing this hypothesis may clarify our understanding of developmental trajectories in music reward valuation, and offer insights into why music from adults' adolescence holds a great deal of personal significance.

More about being fun: Making friends to maximize social status

OBJECTIVE

Children perceived by peers as someone who is fun reap interpersonal rewards, but little is known about what makes someone fun or how being fun leads to social success. The present study is designed to identify what qualities makes someone fun and how being fun leads to social success.

METHOD

Two studies of children in primary and middle school are reported. Participants in the present investigation attended a public-school representative of Florida school children in terms of ethnicity and income. In the first study, 351 (179 girls, 172 boys) students (8-11 years old) completed surveys twice (M = 8.5 weeks apart) during an academic year, describing the qualities of "someone who is fun."

RESULTS

At both time points, kindness and humor were rated as more important than buffoonery. In the second study, 394 (210 girls, 184 boys) students (8-13 years old) completed peer nomination surveys thrice (M = 8.5 weeks apart) during an academic year. Replicating previous findings, being fun predicted increases in social status (i.e., likeability and popularity).

CONCLUSIONS

Unique to this study, full longitudinal mediation analyses indicated that being perceived as fun early in the school year predicted friend gain from the beginning to the middle of the school year, which, in turn, predicted increases in perceived likeability and popularity from the middle to the end of the school year. The findings were unique to being fun. Kindness and humor did not predict friend gain.

Functional connectivity between the nucleus accumbens and amygdala underlies avoidance learning during adolescence: Implications for developmental psychopathology

BACKGROUND

Reward and threat processes work together to support adaptive learning during development. Adolescence is associated with increasing approach behavior (e.g., novelty-seeking, risk-taking) but often also coincides with emerging internalizing symptoms, which are characterized by heightened avoidance behavior. Peaking engagement of the nucleus accumbens (NAcc) during adolescence, often studied in reward paradigms, may also relate to threat mechanisms of adolescent psychopathology.

METHODS

47 typically developing adolescents (9.9-22.9 years) completed an aversive learning task during functional magnetic resonance imaging, wherein visual cues were paired with an aversive sound or no sound. Task blocks involved an escapable aversively reinforced stimulus (CS+r), the same stimulus without reinforcement (CS+nr), or a stimulus that was never reinforced (CS-). Parent-reported internalizing symptoms were measured using Revised Child Anxiety and Depression Scales.

RESULTS

Functional connectivity between the NAcc and amygdala differentiated the stimuli, such that connectivity increased for the CS+r (p = .023) but not for the CS+nr and CS-. Adolescents with greater internalizing symptoms demonstrated greater positive functional connectivity for the CS- (p = .041).

CONCLUSIONS

Adolescents show heightened NAcc-amygdala functional connectivity during escape from threat. Higher anxiety and depression symptoms are associated with elevated NAcc-amygdala connectivity during safety, which may reflect poor safety versus threat discrimination.

Co-rumination between friends: Considering the roles of outcome expectations, relationship provisions, and perceptions of problems

Despite its implications for adjustment, little is known about factors that support co-rumination in friendships. The current multi-method, longitudinal study addressed this question with 554 adolescents (Mage = 14.50; 52% girls; 62% White; 31% Black; 7% Asian American) from the Midwestern United States in 2007-2010. Adolescents were observed talking about problems with a friend and reported on their outcome expectations for problem disclosures, relationship provisions during problem talk, and problem perceptions after problem talk. Participants reported on outcome expectations again 9 months later. Results indicate that the positive relationship provisions associated with co-rumination may outweigh negative problem perceptions in predicting adolescents' outcome expectations for problem disclosures over time. Implications for the potentially reinforcing nature of co-rumination are discussed.

From developmental neuroscience to policy: A novel framework based on participatory research

Insights from developmental neuroscience are not always translated to actionable policy decisions. In this review, we explore the potential of bridging the gap between developmental neuroscience and policy through youth participatory research approaches. As the current generation of adolescents lives in an increasingly complex and rapidly changing society, their lived experiences are crucial for both research and policy. Moreover, their active involvement holds significant promise, given their heightened creativity and need to contribute. We therefore advocate for a transdisciplinary framework that fosters collaboration between developmental scientists, adolescents, and policy makers in addressing complex societal challenges. We highlight the added value of adolescents' lived experiences in relation to two pressing societal issues affecting adolescents' mental health: performance pressure and social inequality. By integrating firsthand lived experiences with insights from developmental neuroscience, we provide a foundation for progress in informed policy decisions.

Unlocking the age-old secrets of reward and substance use

Although substance use is widespread across the lifespan from early adolescence to older adulthood, the prevalence of substance use disorder (SUD) differs between age groups. These age differences in SUD rates necessitate an investigation into how age moderates reward sensitivity, and consequently influences the risks and consequences related to substance use. This theoretical review integrates evidence from the literature to address the dynamic interplay between age and reward in the context of substance use. Overall, increasing evidence demonstrates that age moderates reward sensitivity and underlying reward system neurobiology. Reward sensitivity undergoes a non-linear trajectory across the lifespan. Low levels of reward sensitivity are associated with childhood and late adulthood. In contrast, high levels are associated with early to late adolescence, followed by a decline in the twenties. These fluctuations in reward sensitivity across the lifespan contribute to complex associations with substance use. This lends support to adolescence and young adulthood as vulnerable periods for the risk of subsequent SUD. More empirical research is needed to investigate reward sensitivity during SUD maintenance and recovery. Future research should also involve larger sample sizes and encompass a broader range of age groups, including older adults.

Exposure to community violence as a mechanism linking neighborhood socioeconomic disadvantage and neural responses to reward

A growing literature links socioeconomic disadvantage and adversity to brain function, including disruptions in reward processing. Less research has examined exposure to community violence (ECV) as a specific adversity related to differences in reward-related brain activation, despite the prevalence of community violence exposure for those living in disadvantaged contexts. The current study tested whether ECV was associated with reward-related ventral striatum (VS) activation after accounting for familial factors associated with differences in reward-related activation (e.g. parenting and family income). Moreover, we tested whether ECV is a mechanism linking socioeconomic disadvantage to reward-related activation in the VS. We utilized data from 444 adolescent twins sampled from birth records and residing in neighborhoods with above-average levels of poverty. ECV was associated with greater reward-related VS activation, and the association remained after accounting for family-level markers of disadvantage. We identified an indirect pathway in which socioeconomic disadvantage predicted greater reward-related activation via greater ECV, over and above family-level adversity. These findings highlight the unique impact of community violence exposure on reward processing and provide a mechanism through which socioeconomic disadvantage may shape brain function.

Genetic variation in endocannabinoid signaling: Anxiety, depression, and threat- and reward-related brain functioning during the transition into adolescence

BACKGROUND

The endocannabinoid system modulates neural activity throughout the lifespan. In adults, neuroimaging studies link a common genetic variant in fatty acid amide hydrolase (FAAH C385A)-an enzyme that regulates endocannabinoid signaling-to reduced risk of anxiety and depression, and altered threat- and reward-related neural activity. However, limited research has investigated these associations during the transition into adolescence, a period of substantial neurodevelopment and increased psychopathology risk.

METHODS

This study included FAAH genotype and longitudinal neuroimaging and neurobehavioral data from 4811 youth (46% female; 9-11 years at Baseline, 11-13 years at Year 2) from the Adolescent Brain Cognitive DevelopmentSM Study. Linear mixed models examined the effects of FAAH and the FAAH x time interaction on anxiety and depressive symptoms, amygdala reactivity to threatening faces, and nucleus accumbens (NAcc) response to happy faces during the emotional n-back task.

RESULTS

A significant main effect of FAAH on depressive symptoms was observed, such that depressive symptoms were lower across both timepoints in those with the AA genotype compared to both AC and CC genotypes (p's<0.05). There were no significant FAAH x time interactions for anxiety, depression, or neural responses (p's>0.05). Additionally, there were no main effects of FAAH on anxiety or neural responses (p's>0.05).

CONCLUSIONS

Our findings add to emerging evidence linking the FAAH C385A variant to lower risk of psychopathology, and extend these findings to a developmental sample. In particular, we found lower depressive symptoms in FAAH AA genotypes compared to AC and CC genotypes. Future research is needed to characterize the role of the FAAH variant and the eCB system more broadly in neurodevelopment and psychiatric risk.

A cognitive-computational account of mood swings in adolescence

Teenagers have a reputation for being fickle, in both their choices and their moods. This variability may help adolescents as they begin to independently navigate novel environments. Recently, however, adolescent moodiness has also been linked to psychopathology. Here, we consider adolescents' mood swings from a novel computational perspective, grounded in reinforcement learning (RL). This model proposes that mood is determined by surprises about outcomes in the environment, and how much we learn from these surprises. It additionally suggests that mood biases learning and choice in a bidirectional manner. Integrating independent lines of research, we sketch a cognitive-computational account of how adolescents' mood, learning, and choice dynamics influence each other, with implications for normative and psychopathological development.

Reinforcement sensitivity theory and externalizing problems across early adolescence: Testing within-person reciprocal associations

Temperament and externalizing problems are closely linked, but research on how they codevelop across adolescence remains sparse and equivocal. Reinforcement sensitivity theory (RST) provides a useful framework for understanding temperament and externalizing problems associations. During adolescence, oppositional problems are posited to be linked to an overactive behavioral approach system (BAS) while conduct problems are linked to an underactive behavioral inhibition system (BIS). However, this research mostly uses adult samples and cross-sectional designs and tests only between-person associations. Moreover, most studies typically test only one direction of effects (i.e., temperament predicts externalizing problems) and do not consider alternative models of associations, such as reciprocal associations. To address these limitations, we use three annual waves of a longitudinal, community-based sample of 387 early adolescents (mean Wave 1 age = 11.61 years, 55% female, 83% non-Hispanic White) to test reciprocal associations between BIS and BAS and oppositional and conduct problems. Latent curve models with structured residuals are used to test hypotheses and disaggregate between- and within-person associations. Evidence supports within-person reciprocal associations between BAS and oppositional problems and between BIS and combined conduct and oppositional problems. Results potentially inform developmental theories of temperament and externalizing problems linkages and interventions with adolescents who are engaging in oppositional problems and more severe conduct problems. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Learning whom not to trust across early and middle adolescence: A longitudinal neuroimaging study to trusting behavior involving an uncooperative other

Longitudinal changes in trusting behavior across adolescence and their neural correlates were examined. Neural regions of interest (ROIs) included the medial prefrontal cortex (mPFC), dorsal anterior cingulate cortex (dACC), left anterior insula (AI), bilateral ventral striatum (VS), and right dorsal striatum (DS). Participants (wave 1 age: M = 12.90) played the investor in a Trust Game with an uncooperative trustee three times (1-year interval). Analyses included 77 primarily Dutch participants (33 females). Participants decreased their investments with wave. Furthermore, activity was heightened in mPFC, dACC, and DS during investment and repayment, and in right VS (investment) and AI (repayment). Finally, DS activity during repayment increased with wave. These findings highlight early-middle adolescence as an important period for developing sensitivity to uncooperative behavior.

Early life stress moderates the relation between systemic inflammation and neural activation to reward in adolescents both cross-sectionally and longitudinally

Elevated levels of systemic inflammation are associated with altered reward-related brain function in ventral striatal areas of the brain like the nucleus accumbens (NAcc). In adolescents, cross-sectional research indicates that exposure to early life stress (ELS) can moderate the relation between inflammation and neural activation, which may contribute to atypical reward function; however, no studies have tested whether this moderation by ELS of neuroimmune associations persists over time. Here, we conducted a cross-sectional analysis and the first exploratory longitudinal analysis testing whether cumulative severity of ELS moderates the association of systemic inflammation with reward-related processing in the NAcc in adolescents (n = 104; 58F/46M; M[SD] age = 16.00[1.45] years; range = 13.07-19.86 years). For the cross-sectional analysis, we modeled a statistical interaction between ELS and levels of C-reactive protein (CRP) predicting NAcc activation during the anticipation and outcome phases of a monetary reward task. We found that higher CRP was associated with blunted NAcc activation during the outcome of reward in youth who experienced higher levels of ELS (β = -0.31; p = 0.006). For the longitudinal analysis, we modeled an interaction between ELS and change in CRP predicting change in NAcc activation across 2 years. This analysis similarly showed that increasing CRP over time was associated with decreasing NAcc during reward outcomes in youth who experienced higher levels of ELS (β = -0.47; p = 0.022). Both findings support contemporary theoretical frameworks involving associations among inflammation, reward-related brain function, and ELS exposure, and suggest that experiencing ELS can have significant and enduring effects on neuroimmune function and adolescent neurodevelopment.

The Social Dynamics of Fun: Can Fun Youth Bring Peers Together and Positively Influence Their Friends?

There is a critical gap in our understanding of how peer relationships contribute to positive youth development. To address this gap the current study uses longitudinal social network data to examine if fun youth were socially desirable, inclusive of peers, and positive agents of social influence during the transition to adolescence. Participants were 210 students (47% female; Mage = 11.55 years at the outset) from 8 classes in 3 schools in a small Lithuanian city. Each child received a fun score consisting of nominations from classmates as "someone who is fun to be around". Participants also nominated up to five classmates as friends. Fun students received more friendship nominations than their peers and they maintained higher levels of social desirability over time. Fun youth appeared to be inclusive of their peers in that fun youth did not appear to have preferences to befriend only those like themselves. The friends of fun youth were positively influenced such that they were perceived to be more fun over time. The findings suggests that fun youth may promote positive social change within peer groups.

Transitioning from childhood into adolescence: A comprehensive longitudinal behavioral and neuroimaging study on prosocial behavior and social inclusion

Acting prosocially and feeling socially included are important factors for developing social relations. However, little is known about the development of neural trajectories of prosocial behavior and social inclusion in the transition from middle childhood to early adolescence. In this pre-registered study, we investigated the development of prosocial behavior, social inclusion, and their neural mechanisms in a three-wave longitudinal design (ages 7-13 years; NT1 = 512; NT2 = 456; NT3 = 336). We used the Prosocial Cyberball Game, a ball tossing game in which one player is excluded, to measure prosocial compensating behavior. Prosocial compensating behavior showed a linear developmental increase, similar to parent-reported prosocial behavior, whereas parent-reported empathy showed a quadratic trajectory with highest levels in late childhood. On a neural level we found a peak in ventral striatum activity during prosocial compensating behavior. Neural activity during social inclusion showed quadratic age effects in anterior cingulate cortex, insula, striatum, and precuneus, and a linear increase in temporo-parietal junction. Finally, changes in prosocial compensating behavior were negatively associated with changes in ventral striatum and mPFC activity during social inclusion, indicating an important co-occurrence between development in brain and social behavior. Together these findings shed a light on the mechanisms underlying social development from childhood into adolescence.

Environmental statistics and experience shape risk-taking across adolescence

Adolescents are often portrayed as reckless risk-takers because of their immature brains. Recent research has cast doubt on this portrayal, identifying the environment as a moderator of risk-taking. However, the key features of environments that drive risk-taking behaviors are often underspecified. We call for greater attention to the environment by drawing on research showing that its statistical structure impacts future risk-taking as people learn from outcomes they experience after taking a risk. This opinion shows that adolescents are unlikely to experience harm from many risks because environmental statistics are skewed and favor safe experiences. Environmental statistics and experience suggest entry points for policy interventions by carefully timing risk warnings and leveraging peers' potential to shape the statistics of rewarding experiences.

Striatal correlates of Bayesian beliefs in self-efficacy in adolescents and their relation to mood and autonomy: a pilot study

Major depressive disorder often originates in adolescence and is associated with long-term functional impairment. Mechanistically characterizing this heterogeneous illness could provide important leads for optimizing treatment. Importantly, reward learning is known to be disrupted in depression. In this pilot fMRI study of 21 adolescents (16-20 years), we assessed how reward network disruption impacts specifically on Bayesian belief representations of self-efficacy (SE-B) and their associated uncertainty (SE-U), using a modified instrumental learning task probing activation induced by the opportunity to choose, and an optimal Hierarchical Gaussian Filter computational model. SE-U engaged caudate, nucleus accumbens (NAcc), precuneus, posterior parietal and dorsolateral prefrontal cortex (PFWE < 0.005). Sparse partial least squares analysis identified SE-U striatal activation as associating with one's sense of perceived choice and depressive symptoms, particularly anhedonia and negative feelings about oneself. As Bayesian uncertainty modulates belief flexibility and their capacity to steer future actions, this suggests that these striatal signals may be informative developmentally, longitudinally and in assessing response to treatment.

Understanding patch foraging strategies across development

Patch foraging is a near-ubiquitous behaviour across the animal kingdom and characterises many decision-making domains encountered by humans. We review how a disposition to explore in adolescence may reflect the evolutionary conditions under which hunter-gatherers foraged for resources. We propose that neurocomputational mechanisms responsible for reward processing, learning, and cognitive control facilitate the transition from exploratory strategies in adolescence to exploitative strategies in adulthood - where individuals capitalise on known resources. This developmental transition may be disrupted by psychopathology, as there is emerging evidence of biases in explore/exploit choices in mental health problems. Explore/exploit choices may be an informative marker for mental health across development and future research should consider this feature of decision-making as a target for clinical intervention.

Early life interpersonal stress and depression: Social reward processing as a potential mediator

Experiencing stressful events early in life is lamentably very common and widespread across the globe. Despite the strong link between experiencing such stress and developing depression, the mechanisms underlying this association remain unclear. This review addresses this critical question by drawing focus to "early life interpersonal stress" (ELIS), or stressful experiences that occur within the context of a relationship where there is close, direct interaction. Recent evidence suggests that ELIS uniquely relates to depression. A growing body of work demonstrates that ELIS impacts how youth respond to social reward (e.g., positive social stimuli/ feedback). Similar social reward-related impairments are noted in youth with depression. The current review synthesizes these two disparate, yet related, bodies of literature examining the relations between a) ELIS and neurobehavioral alterations in social reward processing; and b) behavioral and neural processing of social reward in depression. A preliminary model presents neurobehavioral disruptions in social reward processing as one mediating factor underlying the connection between ELIS and depression. Key limitations and future directions are discussed.

Neural processing of observed performance-based errors and rewards in the context of friends and unfamiliar peers across adolescence

Adolescence is characterized by changes in performance monitoring, whereby action outcomes are monitored to subsequently adapt behavior and optimize performance. Observation of performance-based outcomes (i.e., errors and rewards) received by others forms the basis of observational learning. Adolescence is also a period of increasing importance of peers, especially friends, and observing peers forms a crucial aspect of learning in the social context of the classroom. However, to our knowledge, no developmental fMRI studies have examined the neural mechanisms underlying observed performance monitoring of errors and rewards in the context of peers. The current fMRI study investigated the neural correlates of observing performance-based errors and rewards of peers in adolescents aged 9-16 years (N = 80). In the scanner, participants observed either their best friend or an unfamiliar peer play a shooting game resulting in performance-dependent rewards (based on hits) or losses (based on misses, i. e, errors), where outcomes affected both the player and the observing participant. Findings showed higher activation in the bilateral striatum and bilateral anterior insula when adolescents observed peers (i.e., best friend and unfamiliar peer) receive performance-based rewards compared to losses. This might reflect the heightened salience of observed reward processing in the peer context in adolescence. Our results further revealed lower activation in the left temporoparietal junction (TPJ) while adolescents observed the performance-based outcomes (rewards and losses) for their best friend than for an unfamiliar peer. Considering that observation of others' performance-based errors and rewards forms the basis of observational learning, this study provides a crucial first step in understanding and potentially improving adolescent observational learning in the peer context.

The age-varying effects of adolescent stress on impulsivity and sensation seeking

Adolescence is defined in part by heightened exposure and sensitivity to stressors. In a longitudinal cohort of youth at risk for substance use problems, we examined the age-varying relationship between stress exposure and traits that are central to the dual systems model. The positive associations between stress exposure, impulsivity, sensation seeking varied as function of age. Specifically, the influence of stress exposure on impulsivity strengthened during early adolescence and remained stable into early adulthood, while the influence of stress exposure on sensation seeking strengthened from early- to mid-adolescence and weakened thereafter. These findings suggest that the maturational imbalance between the capacity to regulate impulsive tendencies and sensation seeking may be exaggerated for youth who are exposed to a high number of stressors.

Differential processing of risk and reward in delinquent and non-delinquent youth

The present study examined the behavioral and neural differences in risky decision-making between delinquent (n = 23) and non-delinquent (n = 27) youth ages 13-17 years (M = 16, SD = 0.97) in relation to reward processing. While undergoing functional neuroimaging, participants completed an experimental risk task wherein they received feedback about the riskiness of their behavior in the form of facial expressions that morphed from happy to angry. Behavioral results indicated that delinquent youth took fewer risks and earned fewer rewards on the task than non-delinquent youth. Results from whole-brain analyses indicated no group differences in sensitivity to punishments (i.e. angry faces), but instead showed that delinquent youth evinced greater neural tracking of reward outcomes (i.e. cash-ins) in regions including the ventral striatum and inferior frontal gyrus. While behavioral results show that delinquent youth were more risk-averse, the neural results indicated that delinquent youth were also more reward-driven, potentially suggesting a preference for immediate rewards. Results offer important insights into differential decision-making processes between delinquent and non-delinquent youth.

Development and validation of an fMRI-informed EEG model of reward-related ventral striatum activation

Reward processing is essential for our mental-health and well-being. In the current study, we developed and validated a scalable, fMRI-informed EEG model for monitoring reward processing related to activation in the ventral-striatum (VS), a significant node in the brain's reward system. To develop this EEG-based model of VS-related activation, we collected simultaneous EEG/fMRI data from 17 healthy individuals while listening to individually-tailored pleasurable music - a highly rewarding stimulus known to engage the VS. Using these cross-modal data, we constructed a generic regression model for predicting the concurrently acquired Blood-Oxygen-Level-Dependent (BOLD) signal from the VS using spectro-temporal features from the EEG signal (termed hereby VS-related-Electrical Finger Print; VS-EFP). The performance of the extracted model was examined using a series of tests that were applied on the original dataset and, importantly, an external validation dataset collected from a different group of 14 healthy individuals who underwent the same EEG/FMRI procedure. Our results showed that the VS-EFP model, as measured by simultaneous EEG, predicted BOLD activation in the VS and additional functionally relevant regions to a greater extent than an EFP model derived from a different anatomical region. The developed VS-EFP was also modulated by musical pleasure and predictive of the VS-BOLD during a monetary reward task, further indicating its functional relevance. These findings provide compelling evidence for the feasibility of using EEG alone to model neural activation related to the VS, paving the way for future use of this scalable neural probing approach in neural monitoring and self-guided neuromodulation.

Peer facilitation of emotion regulation in adolescence

Emotion regulation is particularly important for adolescents as they undergo normative developmental changes in affective systems and experience heightened risk for psychopathology. Despite a high need for emotion regulation during adolescence, commonly studied emotion regulation strategies like cognitive reappraisal are less beneficial for adolescents than adults because they rely on neural regions that are still developing during this period (i.e., lateral prefrontal cortex). However, adolescence is also marked by increased valuation of peer relationships and sensitivity to social information and cues. In the present review, we synthesize research examining emotion regulation and peer influence across development to suggest that sensitivity to peers during adolescence could be leveraged to improve emotion regulation for this population. We first discuss developmental trends related to emotion regulation at the level of behavior and brain in adolescents, using cognitive reappraisal as an exemplar emotion regulation strategy. Next, we discuss social influences on adolescent brain development, describing caregiver influence and increasing susceptibility to peer influence, to describe how adolescent sensitivity to social inputs represents both a window of vulnerability and opportunity. Finally, we conclude by describing the promise of social (i.e., peer-based) interventions for enhancing emotion regulation in adolescence.

Neural Reactivity to Social Punishment Predicts Future Engagement in Nonsuicidal Self-injury Among Peer-Rejected Adolescents

BACKGROUND

Rates of nonsuicidal self-injury (NSSI) increase dramatically in adolescence. Affective reactivity and adverse social experiences have been linked to NSSI, but less is known about whether these factors may separately or interactively predict NSSI, especially longitudinally. This study combined functional magnetic resonance imaging and a sociometric measure to test whether a combination of neural (e.g., amygdala) reactivity to social punishment and peer-nominated peer acceptance/rejection predicts NSSI longitudinally in adolescence. Amygdala reactivity was examined as a potential neural marker of affective reactivity to social punishment, which may heighten NSSI risk in contexts of social adversity.

METHODS

One hundred twenty-five adolescents (63 female) completed a social incentive delay task during neuroimaging and school-based peer nominations to measure peer acceptance/rejection. NSSI engagement was assessed at baseline and 1-year follow-up.

RESULTS

Greater amygdala reactivity to social punishment predicted greater NSSI engagement 1 year later among adolescents with high peer rejection. This effect for the amygdala was specific to social punishment (vs. reward) and held when controlling for biological sex and pubertal development. Exploratory analyses found that ventral striatum reactivity to social reward and punishment similarly interacted with peer rejection to predict NSSI but that amygdala connectivity with salience network regions did not.

CONCLUSIONS

Amygdala reactivity to social punishment, in combination with high peer rejection, may increase NSSI risk in adolescence, possibly via heightened affective reactivity to adverse social experiences. Objective measures of neurobiological and social risk factors may improve prediction of NSSI, while therapeutic approaches that target affective reactivity and increase prosocial skills may protect against NSSI in adolescence.

Longitudinal neural and behavioral trajectories of charity contributions across adolescence

This study examined the development of prosocial charity donations and neural activity in the ventral striatum when gaining rewards for self and for charity. Participants 10-22 years (95% European heritage) participated in three annual behavioral-fMRI waves (T1: n = 160, T2: n = 167, T3: n = 175). Behaviorally, donations to charity as measured with an economic Dictator Game increased with age. Perspective taking also increased with age. In contrast, self-gain and charity-gain enjoyment decreased with age. Ventral striatum activity was higher for rewards for self than for charity, but this difference decreased during adolescence. Latent growth curve models revealed that higher donations were associated with a smaller difference between ventral striatum activation for self and charity. These findings show longitudinal brain-donations associations in adolescence.

Critical tests of fuzzy trace theory in brain and behavior: uncertainty across time, probability, and development

Uncertainty permeates decisions from the trivial to the profound. Integrating brain and behavioral evidence, we discuss how probabilistic (varied outcomes) and temporal (delayed outcomes) uncertainty differ across age and individuals; how critical tests adjudicate between theories of uncertainty (prospect theory and fuzzy-trace theory); and how these mechanisms might be represented in the brain. The same categorical gist representations of gains and losses account for choices and eye-tracking data in both value-allocation (add money to gambles) and risky-choice tasks, disconfirming prospect theory and confirming predictions of fuzzy-trace theory. The analysis is extended to delay discounting and disambiguated choices, explaining hidden-zero effects that similarly turn on categorical distinctions between some gain and no gain, certain gain and uncertain gain, gain and loss, and now and later. Bold activation implicates dorsolateral prefrontal and posterior parietal cortices in gist strategies that are not just one tool in a grab-bag of cognitive options but rather are general strategies that systematically predict behaviors across many different tasks involving probabilistic and temporal uncertainty. High valuation (e.g., ventral striatum; ventromedial prefrontal cortex) and low executive control (e.g., lateral prefrontal cortex) contribute to risky and impatient choices, especially in youth. However, valuation in ventral striatum supports reward-maximizing and gist strategies in adulthood. Indeed, processing becomes less "rational" in the sense of maximizing gains and more noncompensatory (eye movements indicate fewer tradeoffs) as development progresses from adolescence to adulthood, as predicted. Implications for theoretically predicted "public-health paradoxes" are discussed, including gist versus verbatim thinking in drug experimentation and addiction.

The Effect of Parents and Peers on the Neural Correlates of Risk Taking and Antisocial Behavior During Adolescence

Social and neurobiological factors independently associate with the development of antisocial behavior during adolescence, yet it is unclear how these factors contribute to antisocial behavior in girls. Using a longitudinal sample of 45 adolescent girls (age in years at scan: M = 15.38, SD = 0.33), this study examined the contributions of parent-adolescent relationship quality and deviant peer affiliation from 6th-8th grades along with the neural correlates of risk taking in 9th grade to later antisocial behavior. High parent-adolescent closeness in early adolescence predicted lower antisocial behavior for girls in later adolescence via lower affiliation with deviant peer groups and less activation of the medial prefrontal cortex during risk taking. Findings highlight the enduring role of parents and peers during adolescence, and the importance of investigating social relationships alongside the brain to identify a holistic understanding of the development of antisocial behavior in girls.

Diminished reinforcement sensitivity in adolescence is associated with enhanced response switching and reduced coding of choice probability in the medial frontal pole

Precisely charting the maturation of core neurocognitive functions such as reinforcement learning (RL) and flexible adaptation to changing action-outcome contingencies is key for developmental neuroscience and adjacent fields like developmental psychiatry. However, research in this area is both sparse and conflicted, especially regarding potentially asymmetric development of learning for different motives (obtain wins vs avoid losses) and learning from valenced feedback (positive vs negative). In the current study, we investigated the development of RL from adolescence to adulthood, using a probabilistic reversal learning task modified to experimentally separate motivational context and feedback valence, in a sample of 95 healthy participants between 12 and 45. We show that adolescence is characterized by enhanced novelty seeking and response shifting especially after negative feedback, which leads to poorer returns when reward contingencies are stable. Computationally, this is accounted for by reduced impact of positive feedback on behavior. We also show, using fMRI, that activity of the medial frontopolar cortex reflecting choice probability is attenuated in adolescence. We argue that this can be interpreted as reflecting diminished confidence in upcoming choices. Interestingly, we find no age-related differences between learning in win and loss contexts.

Association between reward-related functional connectivity and tri-level mood and anxiety symptoms

Depression and anxiety are associated with abnormalities in brain regions that process rewards including the medial orbitofrontal cortex (mOFC), the ventral striatum (VS), and the amygdala. However, there are inconsistencies in these findings. This may be due to past reliance on categorical diagnoses that, while valuable, provide less precision than may be required to understand subtle neural changes associated with symptoms of depression and anxiety. In contrast, the tri-level model defines symptom dimensions that are common (General Distress) or relatively specific (Anhedonia-Apprehension, Fears) to depression and anxiety related disorders, which provide increased precision. In the current study, eligibility was assessed by quasi-orthogonal screening questionnaires measuring reward and threat sensitivity (Behavioral Activation Scale; Eysenck Personality Questionnaire-Neuroticism). These participants were assessed on tri-level symptom severity and completed the Monetary Incentive Delay task during fMRI scanning. VS-mOFC and VS-amygdala connectivity were estimated during reward anticipation and reward outcome. Heightened General Distress was associated with lower VS-mOFC connectivity during reward anticipation (b = -0.064, p = 0.021) and reward outcome (b = -0.102, p = 0.014). Heightened Anhedonia-Apprehension was associated with greater VS-amygdala connectivity during reward anticipation (b = 0.065, p = 0.004). The present work has important implications for understanding the coupling between the mOFC and vS and the amygdala and the vS during reward processing in the pathophysiology of mood and anxiety symptoms and for developing targeted behavioral, pharmacological, and neuromodulatory interventions to help manage these symptoms.

Risks and rewards in adolescent decision-making

Adolescent decision-making has been characterized as risky, and a heightened reward sensitivity may be one of the aspects contributing to riskier choice-behavior. Previous studies have targeted reward-sensitivity in adolescence and the neurobiological mechanisms of reward processing in the adolescent brain. In recent examples, researchers aim to disentangle the contributions of risk- and reward-sensitivity to adolescent risk-taking. Here, we discuss recent findings of adolescent's risk preferences and the associated neural mechanisms. We highlight potential frameworks that target individual differences in risk preferences in an effort to understand adolescent risk-taking, and with an ultimate goal of leveraging undesirable levels of risk taking.

Understanding Problematic Social Media Use in Adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD): A Narrative Review and Clinical Recommendations

Attention-Deficit/Hyperactivity Disorder (ADHD) is consistently associated with a host of social problems, such as victimization and difficulties in maintaining close friendships. These problems are not limited to offline relations but also manifest in the online social world, as previous research shows that ADHD is associated with problematic use of social media. Given the ubiquitous nature of social media, the goal of the current review is to understand why adolescents with ADHD demonstrate more problematic social media use than their typically developing peers. To this end, we provide a narrative review on the evidence for the link between ADHD and social media use, and consequently present an integrative framework, which encompasses neurobiological mechanisms (i.e., imbalance theory of brain development and dual pathway model of ADHD) and social mechanisms, including influences from peers and parents. We conclude that empirical work shows most consistent evidence for the link between problematic social media use and ADHD (symptoms), while intensity of social media use is also associated with several other behaviors and outcomes. Finally, we hypothesize how existing interventions for ADHD may work on the identified mechanisms and provide at-hand clinical recommendations for therapists working with adolescents with ADHD who exhibit problematic social media use.

Family History of Depression and Neural Reward Sensitivity: Findings From the Adolescent Brain Cognitive Development Study

BACKGROUND

Previous studies have found that offspring of depressed parents exhibit reduced striatal reward response to anticipating and receiving rewards, suggesting that this may constitute a neurobiological risk marker for depression. The present study aimed to assess whether maternal and paternal depression history have independent effects on offspring reward processing and whether greater family history density of depression is associated with increased blunting of striatal reward responses.

METHODS

Data from the baseline visit of the ABCD (Adolescent Brain Cognitive Development) Study were used. After exclusion criteria, 7233 9- and 10-year-old children (49% female) were included in analyses. Neural responses to reward anticipation and receipt in the monetary incentive delay task were examined in 6 striatal regions of interest. Using mixed-effects models, we evaluated the effect of maternal or paternal depression history on striatal reward response. We also evaluated the effect of family history density on reward response.

RESULTS

Across all 6 striatal regions of interest, neither maternal nor paternal depression significantly predicted blunted response to reward anticipation or feedback. Contrary to hypotheses, paternal depression history was associated with increased response in the left caudate during anticipation, and maternal depression history was associated with increased response in the left putamen during feedback. Family history density was not associated with striatal reward response.

CONCLUSIONS

Our findings suggest that family history of depression is not strongly associated with blunted striatal reward response in 9- and 10-year-old children. Factors contributing to heterogeneity across studies need to be examined in future research to reconcile these results with past findings.

Reward sensitivity modulates the brain reward pathway in stress resilience via the inherent neuroendocrine system

In the previous 10 years, researchers have suggested a critical role for the brain reward system in stress resilience. However, no study has provided an empirical link between activity in the mesostriatal reward regions during stress and the recovery of cortisol stress response. Moreover, although reward sensitivity as a trait has been demonstrated to promote stress resilience, it remains unclear whether it modulates the brain reward system in stress resilience and how this effect is achieved by the inherent neuroendocrine system. To investigate these uncertainties, 70 young adults were recruited to participate in a ScanSTRESS task, and their brain imaging data and saliva samples (for cortisol assay) were collected during the task. In addition, we assessed reward sensitivity, cortisol awakening response, and intrinsic functional connectivity of the brain in all the participants. We found that left putamen activation during stress exposure positively predicted cortisol recovery. In addition, reward sensitivity was positively linked with activation of the left putamen, and this relationship was serially mediated by the cortisol awakening response and right hippocampus-left inferior frontal gyrus intrinsic connectivity. These findings suggest that reward sensitivity modulates reward pathways in stress resilience through the interplay of the diurnal stress response system and network of the hippocampus-prefrontal circuitry. Summarily, the current study built a model to highlight the dynamic and multifaceted interaction between pertinent allostatic factors in the reward-resilience pathway and uncovered new insight into the resilience function of the mesostriatal reward system during stress.

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Cortisol recovery can be predicted by activation of the left putamen in stress.

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Activation of the left putamen was positively linked with reward sensitivity.

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This relationship was serially mediated by the cortisol awakening response and right hippocampus-left inferior frontal gyrus intrinsic coupling.

Reward sensitivity and hazardous alcohol consumption in women: The parallel mediation effect of self-control and impulsivity traits

Introduction: Little research has been carried out on the associations between several individual factors and hazardous alcohol use in women. The aim of this study was first, to study the relationship between reward sensitivity (RS) and alcohol use in both women with and without hazardous drinking separately. Second, to explore the potential mediating roles of the impulsivity and self-control traits in this relationship. Method: The study was analytical and cross-sectional and included 645 female participants (mean age = 19.14; standard deviation (SD)=1.60). All women were divided into two groups (286, 44.3%, with hazardous drinking, HDW; and 359, 55.7%, with light drinking, LDW). Correlation analyses were carried out to explore the associations between the variables, and parallel mediation analyses were performed to investigate the potential mediating roles of impulsivity and self-control in the RS-alcohol use associations in each group separately. Results: A significant association was observed between RS and alcohol use in HDW, contrary to that observed in their counterparts. In addition, both higher impulsivity and less self-control mediated the association between RS and alcohol use only in HDW. Conclusions: Impulsivity and self-control differently affect alcohol use under the condition of high reward sensitivity, only in HDW, suggesting alterations of the dual top-down and bottom-up mechanisms and a possible imbalance between the competing reflexive and impulsive brain systems. More research is needed regarding the individual factors that affect women's drinking to develop sensitive measures for the assessment of alcohol use and more efficient interventions for women.

Individual differences in threat and reward neural circuitry activation: Testing dimensional models of early adversity, anxiety and depression

Altered functioning of the brain's threat and reward circuitry has been linked to early life adversity and to symptoms of anxiety and depression. To date, however, these relationships have been studied largely in isolation and in categorical-based approaches. It is unclear to what extent early life adversity and psychopathology have unique effects on brain functioning during threat and reward processing. We examined functional brain activity during a face processing task in threat (amygdala and ventromedial prefrontal cortex) and reward (ventral striatum and orbitofrontal cortex) regions of interest among a sample (N = 103) of young adults (aged 18-19 years) in relation to dimensional measures of early life adversity and symptoms of anxiety and depression. Results demonstrated a significant association between higher scores on the deprivation adversity dimension and greater activation of reward neural circuitry during viewing of happy faces, with the largest effect sizes observed in the orbitofrontal cortex. We found no significant associations between the threat adversity dimension, or symptom dimensions of anxiety and depression, and neural activation in threat or reward circuitries. These results lend partial support to theories of adversity-related alterations in neural activation and highlight the importance of testing dimensional models of adversity and psychopathology in large sample sizes to further our understanding of the biological processes implicated.

Neural connectivity underlying adolescent social learning in sibling dyads

Social learning theory posits that adolescents learn to adopt social norms by observing the behaviors of others and internalizing the associated outcomes. However, the underlying neural processes by which social learning occurs is less well-understood, despite extensive neurobiological reorganization and a peak in social influence sensitivity during adolescence. Forty-four adolescents (Mage = 12.2 years) completed an fMRI scan while observing their older sibling within four years of age (Mage = 14.3 years) of age complete a risky decision-making task. Group iterative multiple model estimation (GIMME) was used to examine patterns of directional brain region connectivity supporting social learning. We identified group-level neural pathways underlying social observation including the anterior insula to the anterior cingulate cortex and mentalizing regions to social cognition regions. We also found neural states based on adolescent sensitivity to social learning via age, gender, modeling, differentiation, and behavior. Adolescents who were more likely to be influenced elicited neurological up-regulation whereas adolescents who were less likely to be socially influenced elicited neurological down-regulation during risk-taking. These findings highlight patterns of how adolescents process information while a salient influencer takes risks, as well as salient neural pathways that are dependent on similarity factors associated with social learning theory.

Computational modeling reveals strategic and developmental differences in the behavioral impact of reward across adolescence

Studies of reward effects on behavior in adolescence typically rely on performance metrics that confound myriad cognitive and non-cognitive processes, making it challenging to determine which process is impacted by reward. The present longitudinal study applied the diffusion decision model to a reward task to isolate the influence of reward on response caution from influences of processing and motor speed. Participants completed three annual assessments from early to middle adolescence (N = 387, 55% female, M_age  = 12.1 at Wave 1; M_age  = 13.1 at Wave 2, M_age  = 14.1 at Wave 3) and three annual assessments in late adolescence (M_ages  = 17.8, 18.9, 19.9). At each assessment, participants completed a two-choice reaction time task under conditions of no-reward and a block in which points were awarded for speeded accuracy. Reward reduced response caution at all waves, as expected, but had a greater impact as teens moved from early to middle adolescence. Simulations to identify optimal response caution showed that teens were overly cautious in early adolescence but became too focused on speed over accuracy by middle adolescence. By late adolescence, participants adopted response styles that maximized reward. Further, response style was associated with both internalizing and externalizing symptoms in early-to-middle adolescence, providing evidence for the construct validity of a diffusion model approach in this developmental period.

A brief child-friendly reward task reliably activates the ventral striatum in two samples of socioeconomically diverse youth

Adolescence is a period of increased risk-taking behavior, thought to be driven, in part, by heightened reward sensitivity. One challenge of studying reward processing in the field of developmental neuroscience is finding a task that activates reward circuitry, and is short, not too complex, and engaging for youth of a wide variety of ages and socioeconomic backgrounds. In the present study, we tested a brief child-friendly reward task for activating reward circuitry in two independent samples of youth ages 7-19 years old enriched for poverty (study 1: n = 464; study 2: n = 27). The reward task robustly activated the ventral striatum, with activation decreasing from early to mid-adolescence and increasing from mid- to late adolescence in response to reward. This response did not vary by gender, pubertal development, or income-to-needs ratio, making the task applicable for a wide variety of populations. Additionally, ventral striatum activation to the task did not differ between youth who did and did not expect to receive a prize at the end of the task, indicating that an outcome of points alone may be enough to engage reward circuitry. Thus, this reward task is effective for studying reward processing in youth from different socioeconomic backgrounds.

Information about others' choices selectively alters risk tolerance and medial prefrontal cortex activation across adolescence and young adulthood

Adolescence is associated with major changes in the cognitive, emotional and social domains. One domain in which these processes intersect is decision-making. Previous research has shown that individuals' attitudes towards risk and ambiguity shape their decision-making, and information about others' choices can influence individuals' decisions. However, it is currently unknown how information about others' choices influences risk and ambiguity attitudes separately, and the degree to which others' choices shape decision-making differentially across development from adolescence to young adulthood. The current study used a computational modeling framework to test how information about others' choices influences these attitudes. Participants, aged 14-22 years, made a series of risky and ambiguous choices while undergoing fMRI scanning. On some trials, they viewed risky or safe choices of others. Results showed that participants aligned their choices toward the choice preferences of others. Moreover, the tendency to align choices was expressed in changes in risk attitude, but not ambiguity attitude. The change in risk attitude was positively related to neural activation in the medial prefrontal cortex. Results did not show age related differences in behavior and corresponding neural activation, indicating that the manner in which adolescents are influenced by peers is not ubiquitous but rather, is highly context-dependent.

Is Adolescence a Sensitive Period for the Development of Incentive-Reward Motivation?

Human adolescence is broadly construed as a time of heightened risk-taking and a vulnerability period for the emergence of psychopathology. These tendencies have been attributed to the age-related development of neural systems that mediate incentive motivation and other aspects of reward processing as well as individual difference factors that interact with ongoing development. Here, we describe the adolescent development of incentive motivation, which we view as an inherently positive developmental progression, and its associated neural mechanisms. We consider challenges in applying the sensitive period concept to these maturational events and discuss future directions that may help to clarify mechanisms of change.

Adolescent Decision-Making Under Risk: Neural Correlates and Sex Differences

An increased propensity for risk taking is a hallmark of adolescent behavior with significant health and social consequences. Here, we elucidated cortical and subcortical regions associated with risky and risk-averse decisions and outcome evaluation using the Balloon Analog Risk Task in a large sample of adolescents (n = 256, 56% female, age 14 ± 0.6), including the level of risk as a parametric modulator. We also identified sex differences in neural activity. Risky decisions engaged regions that are parts of the salience, dorsal attention, and frontoparietal networks, but only the insula was sensitive to increasing risks in parametric analyses. During risk-averse decisions, the same networks covaried with parametric levels of risk. The dorsal striatum was engaged by both risky and risk-averse decisions, but was not sensitive to escalating risk. Negative-outcome processing showed greater activations than positive-outcome processing. Insula, lateral orbitofrontal cortex, middle, rostral, and superior frontal areas, rostral and caudal anterior cingulate cortex were activated only by negative outcomes, with a subset of regions associated with negative outcomes showing greater activation in females. Taken together, these results suggest that safe decisions are predicted by more accurate neural representation of increasing risk levels, whereas reward-related processes play a relatively minor role.

Social neural sensitivity as a susceptibility marker to family context in predicting adolescent externalizing behavior

Adolescence represents a period of risk for developing patterns of risk-taking and conduct problems, and the quality of the family environment is one robust predictor of such externalizing behavior. However, family factors may not affect all youth uniformly, and individual differences in neurobiological susceptibility to the family context may moderate its influence. The current study investigated brain-based individual differences in social motivational processing as a susceptibility marker to family conflict in predicting externalizing behavior in early adolescent youth. 163 adolescents (M_age = 12.87 years) completed an fMRI scan during which they anticipated social rewards and social punishments. For adolescents with heightened ventral striatum and amygdala blood oxygen-level dependent (BOLD) response during the anticipation of social rewards and heightened ventral striatum BOLD response during the anticipation of social punishments, higher levels of family conflict were associated with greater externalizing behavior. BOLD response when anticipating both social rewards and punishments suggested increased susceptibility to maladaptive family contexts, highlighting the importance of considering adolescent social motivation in positive and negatively valenced contexts.