Feeling left out or just surprised? Neural correlates of social exclusion and overinclusion in adolescence.

Social belonging is an important human drive that influences mood and behavior. Neural responses to social exclusion are well-characterized, but the specificity of these responses to processing rejection-related affective distress is unknown. The present study compares neural responses to exclusion and overinclusion, a condition that similarly violates fairness expectations but does not involve rejection, with a focus on implications for models of dorsal anterior cingulate cortex (dACC) and anterior insula (AI) function. In an fMRI adaptation of the Cyberball paradigm with adolescents aged 11.1-17.7 years (N = 69), we employed parametric modulators to examine scaling of neural signal with cumulative exclusion and inclusion events, an approach that overcomes arbitrary definitions of condition onsets/offsets imposed on fluid, continuous gameplay. We identified positive scaling of dACC and posterior insula response with cumulative exclusion events, but these same regions exhibited trending signal decreases with cumulative inclusion events. Furthermore, areas within the dACC and insula also responded to context incongruency (throws to the participant in the exclusion run; throws between computer players in the overinclusion run). These findings caution against interpretations that responses in these regions uniquely reflect the affective distress of exclusion within social interaction paradigms. We further identified that the left ventrolateral PFC, rostromedial PFC, and left intraparietal sulcus responded similarly to cumulative exclusion and inclusion. These findings shed light on which neural regions exhibit patterns of differential sensitivity to exclusion or overinclusion, as well as those that are more broadly engaged by both types of social interaction.

Novel insights from the Yellow Light Game: Safe and risky decisions differentially impact adolescent outcome-related brain function.

Changes across the span of adolescence in the adolescent reward system are thought to increase the tendency to take risks. While developmental differences in decision and outcome-related reward processes have been studied extensively, existing paradigms have largely neglected to measure how different types of decisions modulate reward-related outcome processes. We modified an existing decision-making paradigm (the Stoplight Task; Chein et al., 2011) to create a flexible laboratory measure of decision-making and outcome processing, including the ability to assess modulatory effects of safe versus risky decisions on reward-related outcome processes: the Yellow Light Game (YLG). We administered the YLG in the MRI scanner to 81 adolescents, ages 11-17 years, recruited from the community. Results showed that nucleus accumbens activation was enhanced for (1) risky > safe decisions, (2) positive > negative outcomes, and (3) outcomes following safe decisions compared to outcomes following risky decisions, regardless of whether these outcomes were positive or negative. Outcomes following risky decisions (compared to outcomes following safe decisions) were associated with enhanced activity in cortical midline structures. Furthermore, while there were no developmental differences in risk-taking behavior, more pubertally mature adolescents showed enhanced nucleus accumbens activation during positive > negative outcomes. These findings suggest that outcome processing is modulated by the types of decisions made by adolescents and highlight the importance of investigating processes involved in safe as well as risky decisions to better understand the adolescent tendency to take risks.