Neural correlates of social exclusion during adolescence: understanding the distress of peer rejection

Regional gray matter volume is associated with rejection sensitivity: a voxel-based morphometry study

Rejection sensitivity (RS) can be defined as the disposition that one tends to anxiously expect, readily perceive, and intensely react to rejection. High-RS individuals are more likely to suffer mental disorders. Previous studies have investigated brain activity during social rejection using different kinds of rejection paradigms and have provided neural evidence of individual differences in response to rejection cues, but the association between individual differences in RS and brain structure has never been investigated. In this study, voxel-based morphometry (VBM) was used to investigate the relationship between gray matter volume (GMV) and RS in a large healthy sample of 150 men and 188 women. The participants completed the RS Questionnaire and underwent an anatomical magnetic resonance imaging scan. Multiple regression was used to analyze the correlation between regional GMV and RS scores, adjusting for age, sex, and total brain GMV. These results showed that GMV in the region of the posterior cingulate cortex/precuneus was negatively associated with RS, and GMV in the region of the inferior temporal gyrus was positively correlated with RS. These findings suggest a relationship between individual differences in RS and GMV in brain regions that are primarily related to social cognition.

Intrapersonal and interpersonal processes of social exclusion

People have a fundamental need to belong with others. Social exclusion impairs this need and has various effects on cognition, affect, and the behavior of excluded individuals. We have previously reported that activity in the dorsal anterior cingulate cortex (dACC) and right ventrolateral prefrontal cortex (rVLPFC) could be a neurocognitive index of social exclusion (Kawamoto et al., 2012). In this article, we provide an integrative framework for understanding occurrences during and after social exclusion, by reviewing neuroimaging, electrophysiological, and behavioral studies of dACC and rVLPFC, within the framework of intrapersonal and interpersonal processes of social exclusion. As a result, we have indicated directions for future studies to further clarify the phenomenon of social exclusion from the following perspectives: (1) constructional elements of social exclusion, (2) detection sensitivity and interpretation bias in social exclusion, (3) development of new methods to assess the reactivity to social exclusion, and (4) sources of social exclusion.

Understanding social hierarchies: The neural and psychological foundations of status perception

Social groups across species rapidly self-organize into hierarchies, where members vary in their level of power, influence, skill, or dominance. In this review, we explore the nature of social hierarchies and the traits associated with status in both humans and nonhuman primates, and how status varies across development in humans. Our review finds that we can rapidly identify social status based on a wide range of cues. Like monkeys, we tend to use certain cues, like physical strength, to make status judgments, although layered on top of these more primitive perceptual cues are sociocultural status cues like job titles and educational attainment. One's relative status has profound effects on attention, memory, and social interactions, as well as health and wellness. These effects can be particularly pernicious in children and adolescents. Developmental research on peer groups and social exclusion suggests teenagers may be particularly sensitive to social status information, but research focused specifically on status processing and associated brain areas is very limited. Recent evidence from neuroscience suggests that there may be an underlying neural network, including regions involved in executive, emotional, and reward processing, that is sensitive to status information. We conclude with questions for future research as well as stressing the need to expand social neuroscience research on status processing to adolescents.

Adolescent-specific patterns of behavior and neural activity during social reinforcement learning

Humans are sophisticated social beings. Social cues from others are exceptionally salient, particularly during adolescence. Understanding how adolescents interpret and learn from variable social signals can provide insight into the observed shift in social sensitivity during this period. The present study tested 120 participants between the ages of 8 and 25 years on a social reinforcement learning task where the probability of receiving positive social feedback was parametrically manipulated. Seventy-eight of these participants completed the task during fMRI scanning. Modeling trial-by-trial learning, children and adults showed higher positive learning rates than did adolescents, suggesting that adolescents demonstrated less differentiation in their reaction times for peers who provided more positive feedback. Forming expectations about receiving positive social reinforcement correlated with neural activity within the medial prefrontal cortex and ventral striatum across age. Adolescents, unlike children and adults, showed greater insular activity during positive prediction error learning and increased activity in the supplementary motor cortex and the putamen when receiving positive social feedback regardless of the expected outcome, suggesting that peer approval may motivate adolescents toward action. While different amounts of positive social reinforcement enhanced learning in children and adults, all positive social reinforcement equally motivated adolescents. Together, these findings indicate that sensitivity to peer approval during adolescence goes beyond simple reinforcement theory accounts and suggest possible explanations for how peers may motivate adolescent behavior.

The comfort of approach: self-soothing effects of behavioral approach in response to meaning violations

People maintain systems of beliefs that provide them with a sense of belongingness, control, identity, and meaning, more generally. Recent research shows that when these beliefs are threatened a syndrome of negatively valenced arousal is evoked that motivates people to seek comfort in their ideologies or other personally valued beliefs. In this paper we will provide an overview of this process and discuss areas for future research. Beginning with the neural foundations of meaning violations, we review findings that show the anterior cingulate cortex is responsible for detecting inconsistencies, and importantly, that this is experienced as aversive. Next, we evaluate the evidential support for a psychophysiological arousal response as measured by cardiography and skin conductance. We discuss how current theorizing proposes that subsequent behavioral approach ameliorates the negative arousal and serves as an effective, well-adapted coping response, but we also aim to further integrate this process in the existing threat-compensation literature. Finally, we speculate on whether approach motivation is likely to result when one feels capable of handling the threat, thereby incorporating the biopsychosocial model that distinguishes between challenge and threat into the motivational threat-response literature. We believe the current literature on threat and meaning has much to offer and we aim to provide new incentives for further development.

The importance of puberty for adolescent development: conceptualization and measurement

How and why are teenagers different from children and adults? A key question concerns the ways in which pubertal development shapes psychological changes in adolescence directly through changes to the brain and indirectly through the social environment. Empirical work linking pubertal development to adolescent psychological function draws from several different perspectives, often with varying approaches and a focus on different outcomes and mechanisms. The main themes concern effects of atypical pubertal timing on behavior problems during adolescence, effects of pubertal status (and associated hormones) on normative changes in behaviors that can facilitate or hinder development (especially risk-taking, social reorientation, and stress responsivity), and the role of puberty in triggering psychopathology in vulnerable individuals. There is also interest in understanding the ways in which changes in the brain reflect pubertal processes and underlie psychological development in adolescence. In this chapter, we consider the ways that puberty might affect adolescent psychological development, and why this is of importance to developmentalists. We describe the processes of pubertal development; summarize what is known about pubertal influences on adolescent development; consider the assumptions that underlie most work and the methodological issues that affect the interpretation of results; and propose research directions to help understand paths from puberty to behavior. Throughout, we emphasize the importance of pubertal change in all aspects of psychological development, and the ways in which puberty represents an opportunity to study the interplay of biological and social influences.

Differential social evaluation of pregnant teens, teen mothers and teen fathers by university students

Youth may be particularly attuned to social evaluation during the teen years with implications for physical and mental health. Negative attitudes and stereotypes constitute an important type of social evaluative threat. Pregnant and parenting teens not only encounter challenges associated with their early transition to parenthood, but also are confronted with unfavourable attitudes of others. A university sample of 255 men and women responded to surveys targeting their feelings and beliefs about pregnant teens, teen mothers and teen fathers. Teen mothers were generally perceived more positively than pregnant teens who were perceived more positively compared to teen fathers. Social evaluations were generally unrelated to respondents' sex or race, but respondents who had contact with a friend or family member who had experienced a teen pregnancy were selectively more positive, as were freshmen compared to seniors. Risks attributed to early childbearing may be exacerbated by negative social evaluations.

"More than skin deep": stress neurobiology and mental health consequences of racial discrimination

Ethnic minority groups across the world face a complex set of adverse social and psychological challenges linked to their minority status, often involving racial discrimination. Racial discrimination is increasingly recognized as an important contributing factor to health disparities among non-dominant ethnic minorities. A growing body of literature has recognized these health disparities and has investigated the relationship between racial discrimination and poor health outcomes. Chronically elevated cortisol levels and a dysregulated hypothalamic-pituitary-adrenal (HPA) axis appear to mediate effects of racial discrimination on allostatic load and disease. Racial discrimination seems to converge on the anterior cingulate cortex (ACC) and may impair the function of the prefrontal cortex (PFC), hence showing substantial similarities to chronic social stress. This review provides a summary of recent literature on hormonal and neural effects of racial discrimination and a synthesis of potential neurobiological pathways by which discrimination affects mental health.

Neural response to social rejection in children with early separation experiences

OBJECTIVE

Nonhuman and human studies have documented the adverse effects of early life stress (ELS) on emotion regulation and underlying neural circuitry. Less is known about how these experiences shape social processes and neural circuitry. In this study, we thus investigated how ELS affects children's perception of, and neural response to, negative social experiences in a social exclusion paradigm (Cyberball).

METHOD

Twenty-five foster or adopted children with ELS (age 10.6 ± 1.8 years, 13 male and 12 female) and 26 matched nonseparated controls (age 10.38 ± 1.7 years, 12 male and 14 female) took part in a Cyberball paradigm during functional magnetic resonance imaging (fMRI).

RESULTS

During peer rejection, children with ELS reported significantly more feelings of exclusion and frustration than nonseparated controls. On the neural level, children with ELS showed reduced activation in the dorsal anterior cingulate cortex (dACC) and dorsolateral prefrontal cortex (dlPFC), and reduced connectivity between dlPFC-dACC, areas previously implicated in affect regulation. Conversely, children with ELS showed increased neural activation in brain regions involved in memory, arousal, and threat-related processing (middle temporal gyrus, thalamus, ventral tegmental area) relative to controls during social exclusion. The number of separation experiences before entering the permanent family predicted reductions in fronto-cingulate recruitment. The relationship between early separations and self-reported exclusion was mediated by dlPFC activity.

CONCLUSION

The findings suggest that ELS leads to alterations in neural circuitry implicated in the regulation of socioemotional processes. This neural signature may underlie foster children's differential reactivity to rejection in everyday life and could increase risk for developing affective disorders.

Measuring neural and behavioral activity during ongoing computerized social interactions: an examination of event-related brain potentials

Social exclusion is a complex social phenomenon with powerful negative consequences. Given the impact of social exclusion on mental and emotional health, an understanding of how perceptions of social exclusion develop over the course of a social interaction is important for advancing treatments aimed at lessening the harmful costs of being excluded. To date, most scientific examinations of social exclusion have looked at exclusion after a social interaction has been completed. While this has been very helpful in developing an understanding of what happens to a person following exclusion, it has not helped to clarify the moment-to-moment dynamics of the process of social exclusion. Accordingly, the current protocol was developed to obtain an improved understanding of social exclusion by examining the patterns of event-related brain activation that are present during social interactions. This protocol allows greater precision and sensitivity in detailing the social processes that lead people to feel as though they have been excluded from a social interaction. Importantly, the current protocol can be adapted to include research projects that vary the nature of exclusionary social interactions by altering how frequently participants are included, how long the periods of exclusion will last in each interaction, and when exclusion will take place during the social interactions. Further, the current protocol can be used to examine variables and constructs beyond those related to social exclusion. This capability to address a variety of applications across psychology by obtaining both neural and behavioral data during ongoing social interactions suggests the present protocol could be at the core of a developing area of scientific inquiry related to social interactions.

It's all in your head - how anticipating evaluation affects the processing of emotional trait adjectives

Language has an intrinsically evaluative and communicative function. Words can serve to describe emotional traits and states in others and communicate evaluations. Using electroencephalography (EEG), we investigate how the cerebral processing of emotional trait adjectives is modulated by their perceived communicative sender in anticipation of an evaluation. 16 students were videotaped while they described themselves. They were told that a stranger would evaluate their personality based on this recording by endorsing trait adjectives. In a control condition a computer program supposedly randomly selected the adjectives. Actually, both conditions were random. A larger parietal N1 was found for adjectives in the supposedly human-generated condition. This indicates that more visual attention is allocated to the presented adjectives when putatively interacting with a human. Between 400 and 700 ms a fronto-central main effect of emotion was found. Positive, and in tendency also negative adjectives, led to a larger late positive potential (LPP) compared to neutral adjectives. A centro-parietal interaction in the LPP-window was due to larger LPP amplitudes for negative compared to neutral adjectives within the ‘human sender’ condition. Larger LPP amplitudes are related to stimulus elaboration and memory consolidation. Participants responded more to emotional content particularly when presented in a meaningful ‘human’ context. This was first observed in the early posterior negativity window (210–260 ms). But the significant interaction between sender and emotion reached only trend-level on post hoc tests. Our results specify differential effects of even implied communicative partners on emotional language processing. They show that anticipating evaluation by a communicative partner alone is sufficient to increase the relevance of particularly emotional adjectives, given a seemingly realistic interactive setting.

Increased neural response to peer rejection associated with adolescent depression and pubertal development

Sensitivity to social evaluation has been proposed as a potential marker or risk factor for depression, and has also been theorized to increase with pubertal maturation. This study utilized an ecologically valid paradigm to test the hypothesis that adolescents with major depressive disorder (MDD) would show altered reactivity to peer rejection and acceptance relative to healthy controls in a network of ventral brain regions implicated in affective processing of social information. A total of 48 adolescents (ages 11-17), including 21 with a current diagnosis of MDD and 27 age- and gender-matched controls, received rigged acceptance and rejection feedback from fictitious peers during a simulated online peer interaction during functional neuroimaging. MDD youth showed increased activation to rejection relative to controls in the bilateral amygdala, subgenual anterior cingulate, left anterior insula and left nucleus accumbens. MDD and healthy youth did not differ in response to acceptance. Youth more advanced in pubertal maturation also showed increased reactivity to rejection in the bilateral amygdala/parahippocampal gyrus and the caudate/subgenual anterior cingulate, and these effects remained significant when controlling for chronological age. Findings suggest that increased reactivity to peer rejection is a normative developmental process associated with pubertal development, but is particularly enhanced among youth with depression.

Adolescent neighborhood quality predicts adult dACC response to social exclusion

Neuroimaging studies using the social-exclusion paradigm Cyberball indicate increased dorsal anterior cingulate cortex (dACC) and right insula activity as a function of exclusion. However, comparatively less work has been done on how social status factors may moderate this finding. This study used the Cyberball paradigm with 85 (45 females) socio-economically diverse participants from a larger longitudinal sample. We tested whether neighborhood quality during adolescence would predict subsequent neural responding to social exclusion in young adulthood. Given previous behavioral studies indicating greater social vigilance and negative evaluation as a function of lower status, we expected that lower adolescent neighborhood quality would predict greater dACC activity during exclusion at young adulthood. Our findings indicate that young adults who lived in low-quality neighborhoods in adolescence showed greater dACC activity to social exclusion than those who lived in higher quality neighborhoods. Lower neighborhood quality also predicted greater prefrontal activation in the superior frontal gyrus, dorsal medial prefrontal cortex and the middle frontal gyrus, possibly indicating greater regulatory effort. Finally, this effect was not driven by subsequent ratings of distress during exclusion. In sum, adolescent neighborhood quality appears to potentiate neural responses to social exclusion in young adulthood, effects that are independent of felt distress.

Electrocortical reactivity to social feedback in youth: a pilot study of the Island Getaway task

Peer relationships become a major concern in adolescence, yet event-related potential (ERP) measures of reactivity to social feedback in adolescence are limited. In this pilot study, we tested a novel task to elicit reactivity to social feedback in youth. Participants (10-15 years old; 57.9% male; N=19) played a game that involved exchanging personal information with peers, voting to remove players from the game, and receiving rejection and acceptance feedback from peers. Results indicated that participants modified their voting behavior in response to peer feedback, and rejection feedback was associated with a negativity in the ERP wave compared to acceptance (i.e., the feedback negativity, FN). The FN predicted behavioral patterns, such that participants who showed greater neural reactivity to social feedback were less likely to reject co-players. Preliminary analyses suggest that the task may be a useful measure of individual differences: adolescents higher in social anxiety symptoms were less likely to reject peers and showed an enhanced FN to rejection vs. acceptance feedback, and higher depressive symptoms predicted an increased FN to rejection specifically. Results suggest that the FN elicited by social feedback may be a useful, economical neural measure of social processing across development and in clinical research.

Cognitive flexibility in adolescence: neural and behavioral mechanisms of reward prediction error processing in adaptive decision making during development

Adolescence is associated with quickly changing environmental demands which require excellent adaptive skills and high cognitive flexibility. Feedback-guided adaptive learning and cognitive flexibility are driven by reward prediction error (RPE) signals, which indicate the accuracy of expectations and can be estimated using computational models. Despite the importance of cognitive flexibility during adolescence, only little is known about how RPE processing in cognitive flexibility deviates between adolescence and adulthood.

In this study, we investigated the developmental aspects of cognitive flexibility by means of computational models and functional magnetic resonance imaging (fMRI). We compared the neural and behavioral correlates of cognitive flexibility in healthy adolescents (12–16 years) to adults performing a probabilistic reversal learning task. Using a modified risk-sensitive reinforcement learning model, we found that adolescents learned faster from negative RPEs than adults. The fMRI analysis revealed that within the RPE network, the adolescents had a significantly altered RPE-response in the anterior insula. This effect seemed to be mainly driven by increased responses to negative prediction errors.

In summary, our findings indicate that decision making in adolescence goes beyond merely increased reward-seeking behavior and provides a developmental perspective to the behavioral and neural mechanisms underlying cognitive flexibility in the context of reinforcement learning.

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Adolescents and adults show differences in processing RPEs.

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Adolescents learn faster from negative prediction errors.

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The anterior insula activation may cause altered sensitivity to RPEs.

The ongoing cognitive processing of exclusionary social events: evidence from event-related potentials

Exclusionary social events are known to cause alterations in neural activity and attention-related processes. However, the precise nature of these neural adjustments remains unknown as previous research has been limited to examining social interactions and exclusionary events as unitary phenomena. To address this limitation, we assessed neural activity during both inclusionary and exclusionary social interactions by examining event-related brain potentials at multiple points within each social event. Our results show an initial enhancement of anterior cingulate cortex -related activation, indexed by the anterior N2, in response to specific exclusionary events followed by an enhanced attentional orienting response, indexed by the P3a, to later segments of each exclusionary event. Decreases in this P3a activation from social inclusion to social exclusion were associated with self-reported increases in anxiety, negative affect, and feelings of depression from inclusion to exclusion. Together, these findings provide novel insights into the dynamic and ongoing neural processes associated with attentional allocation toward social exclusion and the nature of the relationships between neural and behavioral reactions to exclusionary social interactions.

Pupillary motility: bringing neuroscience to the psychiatry clinic of the future

Modern pupillometry has expanded the study and utility of pupil responses in many new domains, including psychiatry, particularly for understanding aspects of cognitive and emotional information processing. Here, we review the applications of pupillometry in psychiatry for understanding patients' information processing styles, predicting treatment, and augmenting function. In the past year pupillometry has been shown to be useful in specifying cognitive/affective occurrences during experimental tasks and informing clinical diagnoses. Such studies demonstrate the potential of pupillary motility to be used in clinical psychiatry much as it has been in neurology for the past century.

Neural changes associated with emotion processing in children experiencing peer rejection: a functional MRI study

This study was performed to investigate differences between children who did and did not experience peer rejection in psychological state through surveys and in emotion processing during an interpersonal stress challenge task to reflect naturalistic interpersonal face-to-face relationships. A total of 20 right-handed children, 10 to 12 yr of age, completed self-rating questionnaires inquiring about peer rejection in school, depression, and anxiety. They then underwent an interpersonal stress challenge task simulating conditions of emotional stress, in reaction to positive, negative and neutral facial expression stimuli, using interpersonal feedbacks, and functional magnetic resonance imaging (FMRI) for an analysis of neural correlates during the task. Ten were the peer-rejection group, whereas the remainder were the control group. Based on the behavioral results, the peer-rejection group exhibited elevated levels of depression, state anxiety, trait anxiety and social anxiety as compared to the control group. The FMRI results revealed that the peer-rejection group exhibited greater and remarkably more extensive activation of brain regions encompassing the amygdala, orbitofrontal cortex and ventrolateral prefrontal cortex in response to negative feedback stimuli of emotional faces. The different brain reactivities characterizing emotion processing during interpersonal relationships may be present between children who do and do not experience peer rejection.

A meta-analysis of the anterior cingulate contribution to social pain

Many functional magnetic resonance imaging studies have explored the neural correlates of social pain that results from social threat, exclusion, rejection, loss or negative evaluation. Although activations have consistently been reported within the anterior cingulate cortex (ACC), it remains unclear which ACC subdivision is particularly involved. To provide a quantitative estimation of the specific involvement of ACC subdivisions in social pain, we conducted a voxel-based meta-analysis. The literature search identified 46 articles that included 940 subjects, the majority of which used the cyberball task. Significant likelihoods of activation were found in both the ventral and dorsal ACC for both social pain elicitation and self-reported distress during social pain. Self-reported distress involved more specifically the subgenual and pregenual ACC than social pain-related contrasts. The cyberball task involved the anterior midcingulate cortex to a lesser extent than other experimental tasks. During social pain, children exhibited subgenual activations to a greater extent than adults. Finally, the ventro-dorsal gradient of ACC activations in cyberball studies was related to the length of exclusion phases. The present meta-analysis contributes to a better understanding of the role of ACC subdivisions in social pain, and it could be of particular importance for guiding future studies of social pain and its neural underpinnings.

Kin rejection: social signals, neural response and perceived distress during social exclusion

Across species, kin bond together to promote survival. We sought to understand the dyadic effect of exclusion by kin (as opposed to non-kin strangers) on brain activity of the mother and her child and their subjective distress. To this end, we probed mother-child relationships with a computerized ball-toss game Cyberball. When excluded by one another, rather than by a stranger, both mothers and children exhibited a significantly pronounced frontal P2. Moreover, upon kin rejection versus stranger rejection, both mothers and children showed incremented left frontal positive slow waves for rejection events. Children reported more distress upon exclusion than their own mothers. Similar to past work, relatively augmented negative frontal slow wave activity predicted greater self-reported ostracism distress. This effect, generalized to the P2, was limited to mother- or child-rejection by kin, with comparable magnitude of effect across kin identity (mothers vs. children). For both mothers and children, the frontal P2 peak was significantly pronounced for kin rejection versus stranger rejection. Taken together, our results document the rapid categorization of social signals as kin relevant and the specificity of early and late neural markers for predicting felt ostracism.

Narcissists' social pain seen only in the brain

Narcissism is a complex phenomenon, involving a level of defensive self-enhancement. Narcissists have avoidant attachment styles, maintain distance in relationships and claim not to need others. However, they are especially sensitive to others' evaluations, needing positive reflected appraisals to maintain their inflated self-views, and showing extreme responses (e.g. aggression) when rejected. The current study tested the hypothesis that narcissists also show hypersensitivity in brain systems associated with distress during exclusion. We measured individual differences in narcissism (Narcissistic Personality Inventory) and monitored neural responses to social exclusion (Cyberball). Narcissism was significantly associated with activity in an a priori anatomically defined social pain network (anterior insula, dorsal anterior cingulate cortex and subgenual anterior cingulate cortex) during social exclusion. Results suggest hypersensitivity to exclusion in narcissists may be a function of hypersensitivity in brain systems associated with distress, and suggests a potential pathway that connects narcissism to negative consequences for longer-term physical and mental health-findings not apparent with self-report alone.

The role of the anterior insula in adolescent decision making

Much recent research on adolescent decision making has sought to characterize the neurobiological mechanisms that underlie the proclivity of adolescents to engage in risky behavior. One class of influential neurodevelopmental models focuses on the asynchronous development of neural systems, particularly those responsible for self-regulation and reward seeking. While this work has largely focused on the development of prefrontal (self-regulation) and striatal (reward processing) circuitry, the present article explores the significance of a different region, the anterior insular cortex (AIC), in adolescent decision making. Although the AIC is known for its role as a cognitive-emotional hub, and is included in some models of adult self-regulation and reward seeking, the importance of the AIC and its maturation in adolescent risk taking has not been extensively explored. In this article we discuss evidence on AIC development, and consider how age-related differences in AIC engagement may contribute to heightened risk taking during adolescence. Based on this review, we propose a model in which the engagement of adolescents in risk taking may be linked in part to the maturation of the AIC and its connectivity to the broader brain networks in which it participates.

Neural responses to exclusion predict susceptibility to social influence

PURPOSE

Social influence is prominent across the lifespan, but sensitivity to influence is especially high during adolescence and is often associated with increased risk taking. Such risk taking can have dire consequences. For example, in American adolescents, traffic-related crashes are leading causes of nonfatal injury and death. Neural measures may be especially useful in understanding the basic mechanisms of adolescents' vulnerability to peer influence.

METHODS

We examined neural responses to social exclusion as potential predictors of risk taking in the presence of peers in recently licensed adolescent drivers. Risk taking was assessed in a driving simulator session occurring approximately 1 week after the neuroimaging session.

RESULTS

Increased activity in neural systems associated with the distress of social exclusion and mentalizing during an exclusion episode predicted increased risk taking in the presence of a peer (controlling for solo risk behavior) during a driving simulator session outside the neuroimaging laboratory 1 week later. These neural measures predicted risky driving behavior above and beyond self-reports of susceptibility to peer pressure and distress during exclusion.

CONCLUSIONS

These results address the neural bases of social influence and risk taking; contribute to our understanding of social and emotional function in the adolescent brain; and link neural activity in specific, hypothesized, regions to risk-relevant outcomes beyond the neuroimaging laboratory. Results of this investigation are discussed in terms of the mechanisms underlying risk taking in adolescents and the public health implications for adolescent driving.

Neural responses to exclusion predict susceptibility to social influence

PURPOSE

Social influence is prominent across the lifespan, but sensitivity to influence is especially high during adolescence and is often associated with increased risk taking. Such risk taking can have dire consequences. For example, in American adolescents, traffic-related crashes are leading causes of nonfatal injury and death. Neural measures may be especially useful in understanding the basic mechanisms of adolescents' vulnerability to peer influence.

METHODS

We examined neural responses to social exclusion as potential predictors of risk taking in the presence of peers in recently licensed adolescent drivers. Risk taking was assessed in a driving simulator session occurring approximately 1 week after the neuroimaging session.

RESULTS

Increased activity in neural systems associated with the distress of social exclusion and mentalizing during an exclusion episode predicted increased risk taking in the presence of a peer (controlling for solo risk behavior) during a driving simulator session outside the neuroimaging laboratory 1 week later. These neural measures predicted risky driving behavior above and beyond self-reports of susceptibility to peer pressure and distress during exclusion.

CONCLUSIONS

These results address the neural bases of social influence and risk taking; contribute to our understanding of social and emotional function in the adolescent brain; and link neural activity in specific, hypothesized, regions to risk-relevant outcomes beyond the neuroimaging laboratory. Results of this investigation are discussed in terms of the mechanisms underlying risk taking in adolescents and the public health implications for adolescent driving.

Self-enhancement influences medial frontal cortex alpha power to social rejection feedback

Although previous research has demonstrated that individuals are motivated to self-enhance, the neurocognitive mechanisms and temporal dynamics of self-enhancement are poorly understood. The current research examined whether self-enhancing motivations affect the perceptual processing of social feedback. Participants who varied in self-enhancement motivations received accept and reject feedback while EEG was recorded. Following this task, we measured perceptions of feedback by asking participants to estimate the number of times they were rejected. Source localization and time-frequency analyses revealed that alpha power in the medial frontal cortex (MFC) completely mediated the relationship between self-enhancement motivations and rejection estimates. Specifically, greater self-enhancement motivations predicted decreased MFC alpha power to reject compared to accept feedback, which predicted decreased rejection estimates. These findings suggest that self-enhancement motivations decrease perception of social rejection by influencing how the MFC processes social feedback.

Acting on social exclusion: neural correlates of punishment and forgiveness of excluders

This functional magnetic resonance imaging study examined the neural correlates of punishment and forgiveness of initiators of social exclusion (i.e. 'excluders'). Participants divided money in a modified Dictator Game between themselves and people who previously either included or excluded them during a virtual ball-tossing game (Cyberball). Participants selectively punished the excluders by decreasing their outcomes; even when this required participants to give up monetary rewards. Punishment of excluders was associated with increased activation in the pre-supplementary motor area (pre-SMA) and bilateral anterior insula. Costly punishment was accompanied by higher activity in the pre-SMA compared with punishment that resulted in gains or was non-costly. Refraining from punishment (i.e. forgiveness) was associated with self-reported perspective-taking and increased activation in the bilateral temporoparietal junction, dorsomedial prefrontal cortex, dorsal anterior cingulate cortex, and ventrolateral and dorsolateral prefrontal cortex. These findings show that social exclusion can result in punishment as well as forgiveness of excluders and that separable neural networks implicated in social cognition and cognitive control are recruited when people choose either to punish or to forgive those who excluded them.

Empathy for social exclusion involves the sensory-discriminative component of pain: a within-subject fMRI study

Recent research has shown that experiencing events that represent a significant threat to social bonds activates a network of brain areas associated with the sensory-discriminative aspects of pain. In the present study, we investigated whether the same brain areas are involved when witnessing social exclusion threats experienced by others. Using a within-subject design, we show that an ecologically valid experience of social exclusion recruits areas coding the somatosensory components of physical pain (posterior insular cortex and secondary somatosensory cortex). Furthermore, we show that this pattern of activation not only holds for directly experienced social pain, but also during empathy for social pain. Finally, we report that subgenual cingulate cortex is the only brain area conjointly active during empathy for physical and social pain. This supports recent theories that affective processing and homeostatic regulation are at the core of empathic responses.

Cognitive conflict links behavioral inhibition and social problem solving during social exclusion in childhood

Behavioral inhibition (BI) is a temperament characterized by heightened negative affect and social reticence to unfamiliar peers. In a longitudinal study, 291 infants were assessed for BI at 24 and 36 months of age. At age 7, N2 amplitude was measured during a Flanker task. Also at age 7, children experienced social exclusion in the lab during an interaction with an unfamiliar peer and an experimenter. Our findings indicate that children characterized as high in BI, relative to those low in BI, had larger (i.e., more negative) N2 amplitudes. Additionally, among children with a large N2, BI was positively related to withdrawal and negatively related to assertiveness during social exclusion. These findings suggest that variations in conflict detection among behaviorally inhibited children plays a role in their social behavior during stressful social situations.

Associations between maternal negative affect and adolescent's neural response to peer evaluation

Parenting is often implicated as a potential source of individual differences in youths' emotional information processing. The present study examined whether parental affect is related to an important aspect of adolescent emotional development, response to peer evaluation. Specifically, we examined relations between maternal negative affect, observed during parent-adolescent discussion of an adolescent-nominated concern with which s/he wants parental support, and adolescent neural responses to peer evaluation in 40 emotionally healthy and depressed adolescents. We focused on a network of ventral brain regions involved in affective processing of social information: the amygdala, anterior insula, nucleus accumbens, and subgenual anterior cingulate, as well as the ventrolateral prefrontal cortex. Maternal negative affect was not associated with adolescent neural response to peer rejection. However, longer durations of maternal negative affect were associated with decreased responsivity to peer acceptance in the amygdala, left anterior insula, subgenual anterior cingulate, and left nucleus accumbens. These findings provide some of the first evidence that maternal negative affect is associated with adolescents' neural processing of social rewards. Findings also suggest that maternal negative affect could contribute to alterations in affective processing, specifically, dampening the saliency and/or reward of peer interactions during adolescence.

Adolescent peer-rejection persistently alters pain perception and CB1 receptor expression in female rats

Peer-interactions are particularly important during adolescence and teenagers display enhanced sensitivity toward rejection by peers. Social rejection has been shown to induce alterations in pain perception in humans. However, the neurobiological consequences of adolescent social rejection have yet to be extensively characterized, and no appropriate animal model is available. Here, we propose inadequate playful interactions in adolescent rats as a novel animal model for social peer-rejection and examine potential long-term consequences into adulthood. Acute social pairing of female adolescent Wistar rats with an age-matched rat from the less playful Fischer344 strain was found to alter social play and decrease pain reactivity, indicating Fischer rats as inadequate social partners for Wistar animals. Therefore, in a second experiment, adolescent female Wistar rats were either reared with another Wistar rat (adequate social rearing; control) or with a Fischer rat (inadequate social rearing; play-deprived). Beginning on day 50, all Wistar rats were group housed with same-strain partners and tested for behavioral, neurobiological and endocrine differences in adulthood. Playful peer-interactions were decreased during adolescence in play-deprived animals, without affecting social contact behavior. Consequently, adult play-deprived rats showed decreased pain sensitivity and increased startle reactivity compared to controls, but did not differ in activity, anxiety-related behavior or social interaction. Both groups also differed in their endocrine stress-response, and expression levels of the cannabinoid CB1 receptor were increased in the thalamus, whereas FAAH levels were decreased in the amygdala. The present animal model therefore represents a novel approach to assess the long-term consequences of peer-rejection during adolescence.

Childhood emotional maltreatment severity is associated with dorsal medial prefrontal cortex responsivity to social exclusion in young adults

Children who have experienced chronic parental rejection and exclusion during childhood, as is the case in childhood emotional maltreatment, may become especially sensitive to social exclusion. This study investigated the neural and emotional responses to social exclusion (with the Cyberball task) in young adults reporting childhood emotional maltreatment. Using functional magnetic resonance imaging, we investigated brain responses and self-reported distress to social exclusion in 46 young adult patients and healthy controls (mean age = 19.2±2.16) reporting low to extreme childhood emotional maltreatment. Consistent with prior studies, social exclusion was associated with activity in the ventral medial prefrontal cortex and posterior cingulate cortex. In addition, severity of childhood emotional maltreatment was positively associated with increased dorsal medial prefrontal cortex responsivity to social exclusion. The dorsal medial prefrontal cortex plays a crucial role in self-and other-referential processing, suggesting that the more individuals have been rejected and maltreated in childhood, the more self- and other- processing is elicited by social exclusion in adulthood. Negative self-referential thinking, in itself, enhances cognitive vulnerability for the development of psychiatric disorders. Therefore, our findings may underlie the emotional and behavioural difficulties that have been reported in adults reporting childhood emotional maltreatment.

Adolescent depression: stress and reward dysfunction

After participating in this educational activity, the physician should be better able to 1. Evaluate the relationship between reward processes, stress, and depression. 2. Assess the characteristics of the three etiological models of stress and reward processes. 3. Identify the biological basis for stress and reward processes. Adolescence is a peak period for the onset of depression, and it is also a time marked by substantial stress as well as neural development within the brain reward circuitry. In this review, we provide a selective overview of current animal and human research investigating the relationship among reward processes, stress, and depression. Three separate, but related, etiological models examine the differential roles that stress may play in relation to reward dysfunction and adolescent depression. First, the reward mediation model suggests that both acute and chronic stress contribute to reward deficits, which, in turn, potentiate depressive symptoms or increase the risk for depression. Second, in line with the stress generation perspective, it is plausible that premorbid reward-related dysfunction generates stress--in particular, interpersonal stress--which then leads to the manifestation of depressive symptoms. Third, consistent with a diathesis-stress model, the interaction between stress and premorbid reward dysfunction may contribute to the onset of depression. Given the equifinal nature of depression, these models could shed important light on different etiological pathways during adolescence, particularly as they may relate to understanding the heterogeneity of depression. To highlight the translational potential of these insights, a hypothetical case study is provided as a means of demonstrating the importance of targeting reward dysfunction in both assessment and treatment of adolescent depression.

Psychobiological mechanisms underlying the social buffering of the hypothalamic-pituitary-adrenocortical axis: a review of animal models and human studies across development

Discovering the stress-buffering effects of social relationships has been one of the major findings in psychobiology in the last century. However, an understanding of the underlying neurobiological and psychological mechanisms of this buffering is only beginning to emerge. An important avenue of this research concerns the neurocircuitry that can regulate the activity of the hypothalamic-pituitary-adrenocortical (HPA) axis. The present review is a translational effort aimed at integrating animal models and human studies of the social regulation of the HPA axis from infancy to adulthood, specifically focusing on the process that has been named social buffering. This process has been noted across species and consists of a dampened HPA axis stress response to threat or challenge that occurs with the presence or assistance of a conspecific. We describe aspects of the relevant underlying neurobiology when enough information exists and expose major gaps in our understanding across all domains of the literatures we aimed to integrate. We provide a working conceptual model focused on the role of oxytocinergic systems and prefrontal neural networks as 2 of the putative biological mediators of this process, and propose that the role of early experiences is critical in shaping later social buffering effects. This synthesis points to both general future directions and specific experiments that need to be conducted to build a more comprehensive model of the HPA social buffering effect across the life span that incorporates multiple levels of analysis: neuroendocrine, behavioral, and social.

Bolstering system-justifying beliefs in response to social exclusion

Integrating research on social exclusion with the broader literature on system justification and flexible responses to threats, we propose a novel coping strategy that individuals may use in the face of social exclusion. In particular, we suggest that because exclusion often feels unexpected, it will lead individuals to bolster the system-justifying worldview that people get what they deserve, as excluded individuals attempt to cognitively cope with the threatened order and predictability of their world. Supporting our prediction, in Study 1, social exclusion (vs. inclusion) led participants to increasingly endorse descriptive meritocratic beliefs suggesting that hard work leads to success in society. This effect was mediated by the perceived unexpectedness of the interaction outcome, providing key evidence for our hypothesized process. Study 2 used individual differences in rejection sensitivity to provide further support for our unexpectedness account, demonstrating that exclusion heightens meritocratic beliefs only insofar as participants tend to find exclusions unexpected. The results expand our understanding of the cognitive mechanisms by which people cope with social exclusion and highlight the malleability of system-justifying ideologies in response to interpersonal factors.

Dopamine receptor D4 gene moderates the effect of positive and negative peer experiences on later delinquency: The Tracking Adolescents' Individual Lives Survey study

The quality of adolescents' relationships with peers can have a lasting impact on later psychosocial adjustment, mental health, and behavior. However, the effect of peer relations on later problem behavior is not uniformly strong, and genetic factors might influence this association. This study used four-wave longitudinal (11–19 years) data (n = 1,151) from the Tracking Adolescents' Individual Lives Survey, a Dutch cohort study into adolescent development to test whether the dopamine receptor D4 polymorphism moderates the impact of negative (i.e., victimization) and positive peer experiences (i.e., social well-being) on later delinquency. Contrary to our expectations, results showed that carriers of the dopamine receptor D4 gene 4-repeat homozygous variant instead of those carrying the 7-repeat allele were more susceptible to the effects of both peer victimization and social well-being on delinquency later in adolescence. Findings of our study are discussed in light of other studies into genetic moderation of peer effects on adolescent development and the possibility that developmental specifics in adolescence, such as maturation processes in brain structure and functioning, may affect the interplay of environmental and genetic factors in this period in life.

Response of the μ-opioid system to social rejection and acceptance

The endogenous opioid system, which alleviates physical pain, is also known to regulate social distress and reward in animal models. To test this hypothesis in humans (n=18), we used an μ-opioid receptor (MOR) radiotracer to measure changes in MOR availability in vivo with positron emission tomography during social rejection (not being liked by others) and acceptance (being liked by others). Social rejection significantly activated the MOR system (i.e., reduced receptor availability relative to baseline) in the ventral striatum, amygdala, midline thalamus and periaqueductal gray (PAG). This pattern of activation is consistent with the hypothesis that the endogenous opioids have a role in reducing the experience of social pain. Greater trait resiliency was positively correlated with MOR activation during rejection in the amygdala, PAG and subgenual anterior cingulate cortex (sgACC), suggesting that MOR activation in these areas is protective or adaptive. In addition, MOR activation in the pregenual ACC was correlated with reduced negative affect during rejection. In contrast, social acceptance resulted in MOR activation in the amygdala and anterior insula, and MOR deactivation in the midline thalamus and sgACC. In the left ventral striatum, MOR activation during acceptance predicted a greater desire for social interaction, suggesting a role for the MOR system in social reward. The ventral striatum, amygdala, midline thalamus, PAG, anterior insula and ACC are rich in MORs and comprise a pathway by which social cues may influence mood and motivation. MOR regulation of this pathway may preserve and promote emotional well being in the social environment.

There and up again: on the uses and misuses of neuroimaging in psychology

The aim of this article is to discuss the conditions under which functional neuroimaging can contribute to the study of higher cognition. We begin by presenting two case studies--on moral and economic decision making--which will help us identify and examine one of the main ways in which neuroimaging can help advance the study of higher cognition. We agree with critics that functional magnetic resonance imaging (fMRI) studies seldom "refine" or "confirm" particular psychological hypotheses, or even provide details of the neural implementation of cognitive functions. However, we suggest that neuroimaging can support psychology in a different way--namely, by selecting among competing hypotheses of the cognitive mechanisms underlying some mental function. One of the main ways in which neuroimaging can be used for hypothesis selection is via reverse inferences, which we here examine in detail. Despite frequent claims to the contrary, we argue that successful reverse inferences do not assume any strong or objectionable form of reductionism or functional locationism. Moreover, our discussion illustrates that reverse inferences can be successful at early stages of psychological theorizing, when models of the cognitive mechanisms are only partially developed.

Psychological, endocrine and neural responses to social evaluation in subclinical depression

This study aimed to identify vulnerability patterns in psychological, physiological and neural responses to mild psychosocial challenge in a population that is at a direct risk of developing depression, but who has not as yet succumbed to the full clinical syndrome. A group of healthy and a group of subclinically depressed participants underwent a modified Montreal Imaging Stress task (MIST), a mild neuroimaging psychosocial task and completed state self-esteem and mood measures. Cortisol levels were assessed throughout the session. All participants showed a decrease in performance self-esteem levels following the MIST. Yet, the decline in performance self-esteem levels was associated with increased levels of anxiety and confusion in the healthy group, but increased levels of depression in the subclinical group, following the MIST. The subclinical group showed overall lower cortisol levels compared with the healthy group. The degree of change in activity in the subgenual anterior cingulate cortex in response to negative evaluation was associated with increased levels of depression in the whole sample. Findings suggest that even in response to a mild psychosocial challenge, those individuals vulnerable to depression already show important maladaptive response patterns at psychological and neural levels. The findings point to important targets for future interventions.

The role of peer rejection in adolescent depression

Adolescence is a period of major risk for depression, which is associated with negative personal, social, and educational outcomes. Yet, in comparison to adult models of depression, very little is known about the specific psychosocial stressors that contribute to adolescent depression, and whether these can be targeted by interventions. In this review, we consider the role of peer rejection. First, we present a comprehensive review of studies using innovative experimental paradigms to understand the role of peer rejection in adolescent depression. We show how reciprocal relationships between peer rejection and depressive symptoms across adolescence powerfully shape and maintain maladaptive trajectories. Second, we consider how cognitive biases and their neurobiological substrates may explain why some adolescents are more vulnerable to the effects of, and perhaps exposure to, peer rejection compared to others. Finally, we draw attention to emerging cognitive and functional magnetic resonance imaging-based neurofeedback training, which by modifying aspects of information processing may promote more adaptive responses to peer rejection. A better understanding of the mechanisms underlying adolescent depression may not only alleviate symptoms during a period of substantial developmental challenges, but may also reduce the burden of the disorder across the lifespan.

Neuroimaging studies of pediatric social anxiety: paradigms, pitfalls and a new direction for investigating the neural mechanisms

Social Anxiety Disorder (SAD) is a common and debilitating condition that typically manifests in adolescence. Here we describe cognitive factors engaged by brain-imaging tasks, which model the peer-based social interactions that evoke symptoms of SAD. We then present preliminary results from the Virtual School paradigm, a novel peer-based social interaction task. This paradigm is designed to investigate the neural mechanisms mediating individual differences in social response flexibility and in participants' responses to uncertainty in social contexts. We discuss the utility of this new paradigm for research on brain function and developmental psychopathology.

Neural responses to witnessing peer rejection after being socially excluded: fMRI as a window into adolescents' emotional processing

During adolescence, concerns about peer rejection and acceptance become increasingly common. Adolescents regularly experience peer rejection firsthand and witness these behaviors among their peers. In the current study, neuroimaging techniques were employed to conduct a preliminary investigation of the affective and cognitive processes involved in witnessing peer acceptance and rejection - specifically when these witnessed events occur in the immediate aftermath of a firsthand experience with rejection. During an fMRI scan, 23 adolescents underwent a simulated experience of firsthand peer rejection. Then, immediately following this experience they watched as another adolescent was ostensibly first accepted and then rejected. Findings indicated that in the immediate aftermath of being rejected by peers, adolescents displayed neural activity consistent with distress when they saw another peer being accepted, and neural activity consistent with emotion regulation and mentalizing (e.g. perspective-taking) processes when they saw another peer being rejected. Furthermore, individuals displaying a heightened sensitivity to firsthand rejection were more likely to show neural activity consistent with distress when observing a peer being accepted. Findings are discussed in terms of how witnessing others being accepted or rejected relates to adolescents' interpretations of both firsthand and observed experiences with peers. In addition, the potential impact that witnessed events might have on the broader perpetuation of bullying at this age is also considered.