Social brain development and the affective consequences of ostracism in adolescence

Impact of simulated ostracism on overweight and normal-weight youths' motivation to eat and food intake

There is growing evidence that the experience of being ostracized can impair individuals' abilities to self-regulate, which in turn, leads to negative health behaviors, such as increased unhealthy eating. Research has focused on adults, but deficits in eating regulation in response to ostracism may be particularly detrimental for overweight or obese youth. This study examines the effects of a brief episode of ostracism on the motivation to eat and food intake of overweight and normal-weight young adolescents (M age=13.6 years). A computerized ball-tossing game (Cyberball) was used to induce ostracism or inclusion. Following the inclusion/ostracism manipulation, all participants completed an operant computer task to earn points exchangeable for portions of food or for time socializing with an unfamiliar peer. Participants' responses for food and their subsequent energy intake were recorded. As hypothesized, ostracized overweight participants responded more for food and had a greater energy intake than overweight participants in the inclusion/control condition; whereas this was not the case for normal-weight participants. These results are important as studies indicate that overweight and obese youth may be at risk of social isolation and peer difficulties. Social adversity, if left unchanged, may increase the difficulty of promoting long-term changes in overweight youths' health behaviors.

Dissociable brain mechanisms for processing social exclusion and rule violation

Social exclusion inherently involves an element of expectancy violation, in that we expect other people to follow the unwritten rule to include us in social interactions. In this functional magnetic resonance imaging (fMRI) study, we employed a unique modification of an interactive virtual ball-tossing game called "Cyberball" (Williams et al., 2000) and a novel paradigm called "Cybershape," in which rules are broken in the absence of social exclusion, to dissociate brain regions that process social exclusion from rule violations more generally. Our Cyberball game employed an alternating block design and removed evoked responses to events when the participant was throwing the ball in inclusion to make this condition comparable to exclusion, where participants did not throw. With these modifications, we replicated prior findings of ventral anterior cingulate cortex (vACC), insula, and posterior cingulate cortex activity evoked by social exclusion relative to inclusion. We also identified exclusion-evoked activity in the hippocampi, left ventrolateral prefrontal cortex, and left middle temporal gyrus. Comparing social exclusion and rule violation revealed a functional dissociation in the active neural systems as well as differential functional connectivity with vACC. Some overlap was observed in regions differentially modulated by social exclusion and rule violation, including the vACC and lateral parietal cortex. These overlapping brain regions showed different activation during social exclusion compared to rule violation, each relative to fair play. Comparing activation patterns to social exclusion and rule violation allowed for the dissociation of brain regions involved in the experience of exclusion versus expectancy violation.

Developmental influences on the neural bases of responses to social rejection: implications of social neuroscience for education

Relational aggression such as social rejection is common within school peer groups. Converging evidence suggests that adolescent females are particularly sensitive to social rejection. We used a novel fMRI adaptation of the Cyberball social rejection paradigm to investigate the neural response to social rejection in 19 mid-adolescent (aged 14-16) and 16 adult female participants. Across all participants, social exclusion (relative to inclusion) elicited a response in bilateral medial prefrontal cortex (mPFC) extending into ventral and subgenual anterior cingulate cortex and medial orbitofrontal cortex; and the left ventrolateral PFC (vlPFC); regions that have been associated in previous studies with social evaluation, negative affective processing, and affect regulation respectively. However, the exclusion-related response in right vlPFC, a region associated in previous studies with the regulation of rejection-related distress, was attenuated in adolescents. Within mPFC, greater activation during exclusion vs. inclusion was associated with greater self-reported susceptibility to peer influence in adolescents but not in adults. This suggests that the brain's response to experimentally-induced social rejection relates to adolescent behaviour in real-world social interactions. We speculate about the potential implications of these findings for educational settings. In particular, functional development of affective circuitry during adolescence may influence social interaction within the school peer group.

Effects of age and MAOA genotype on the neural processing of social rejection

Adolescents are often sensitive to peer rejection, a factor that might contribute to the risk of affective disorder in this age group. Previous studies suggest a significant overlap among socioaffective brain regions involved in the response to social rejection, regions continuing to develop functionally during adolescence and regions influenced by monoamine oxidase A (MAOA) polymorphism. The current study investigated whether the neural response to social rejection is functionally immature in adolescents compared with adults, and whether these responses are modulated by MAOA genotype. Blood-oxygen-level-dependent response was measured with functional magnetic resonance imaging during a rejection-themed emotional Stroop task in 19 adolescents (aged 14-16) and 16 adults (aged 23-28) genotyped for MAOA polymorphism. Similar numbers of MAOA-L and MAOA-H carriers were recruited to maximize power to detect genotype effects. Main effects of rejection stimuli (relative to neutral and acceptance control stimuli) were seen in predicted socioaffective brain regions. Adolescents did not show the adult pattern of modulation by rejection stimuli in the right ventrolateral prefrontal cortex, suggesting continued functional maturation of this regulatory region during adolescence. Age and genotype interacted in the left amygdala, in which the predicted effect of genotype on responses to rejection stimuli was seen in the adults, but not in the adolescents. The data suggest continued functional development of the circuitry underlying the processing of social rejection between adolescence and adulthood, and show that the effects of MAOA genotype on neural responses may vary with age.

Gray matter loss in young relatives at risk for schizophrenia: relation with prodromal psychopathology

The maturation of neocortical regions mediating social cognition during adolescence and young adulthood in relatives of schizophrenia patients may be vulnerable to heritable alterations of neurodevelopment. Prodromal psychotic symptoms, commonly emerging during this period in relatives, have been hypothesized to result from alterations in brain regions mediating social cognition. We hypothesized these regions to show longitudinal alterations and these alterations to predict prodromal symptoms in adolescent and young adult relatives of schizophrenia patients. 27 Healthy controls and 23 relatives were assessed at baseline and one-year follow-up using scale of prodromal symptoms and gray matter volumes of hypothesized regions from T1-MRI images. Regional volumes showing deficits on ANCOVA and repeated-measures ANCOVAs (controlling intra cranial volume, age and gender) were correlated with prodromal symptoms. At baseline, bilateral amygdalae, bilateral pars triangulares, left lateral orbitofrontal, right frontal pole, angular and supramarginal gyrii were smaller in relatives compared to controls. Relatives declined but controls increased or remained stable on bilateral lateral orbitofrontal, left rostral anterior cingulate, left medial prefrontal, right inferior frontal gyrus and left temporal pole volumes at follow-up relative to baseline. Smaller volumes predicted greater severity of prodromal symptoms at both cross-sectional assessments. Longitudinally, smaller baseline volumes predicted greater prodromal symptoms at follow-up; greater longitudinal decreases in volumes predicted worsening (increase) of prodromal symptoms over time. These preliminary findings suggest that abnormal longitudinal gray matter loss may occur in regions mediating social cognition and may convey risk for prodromal symptoms during adolescence and early adulthood in individuals with a familial diathesis for schizophrenia.

Staging perspectives in neurodevelopmental aspects of neuropsychiatry: agents, phases and ages at expression

Neurodevelopmental risk factors have assumed a critical role in prevailing notions concerning the etiopathogenesis of neuropsychiatric disorders. Staging, diagnostic elements at which phase of disease is determined, provides a means of conceptualizing the degree and extent of factors affecting brain development trajectories, but is concurrently specified through the particular interactions of genes and environment unique to each individual case. For present purposes, staging perspectives in neurodevelopmental aspects of the disease processes are considered from conditions giving rise to neurodevelopmental staging in affective states, adolescence, dopamine disease states, and autism spectrum disorders. Three major aspects influencing the eventual course of individual developmental trajectories appear to possess an essential determinant influence upon outcome: (i) the type of agent that interferes with brain development, whether chemical, immune system activating or absent (anoxia/hypoxia), (ii) the phase of brain development at which the agent exerts disruption, whether prenatal, postnatal, or adolescent, and (iii) the age of expression of structural and functional abnormalities. Clinical staging may be assumed at any or each developmental phase. The present perspective offers both a challenge to bring further order to diagnosis, intervention, and prognosis and a statement regarding the extreme complexities and interwoven intricacies of epigenetic factors, biomarkers, and neurobehavioral entities that aggravate currents notions of the neuropsychiatric disorders.