Reduced amygdala habituation to anticipated social rejection in youth with major depressive disorder.

In addition to its risks for morbidity and mortality, adolescent-onset depression is considered a chronic threat to youth's socioemotional development due to its potential disruption of social learning processes. Prior work has determined that youth with depression, or at-risk of developing depression due to familial history, show atypical neural responses to social feedback by peers. To better understand whether adolescents at varying levels of risk for depression show differential neural indices of social learning, the current study interrogated trial-by-trial patterns of youth's neural habituation to repeated social feedback. Seventy-six 10- to 17-year-old girls (22 diagnosed with major depressive disorder [MDD], 30 at familial risk but without MDD, 24 without MDD or familial risk) completed a chatroom task in which they repeatedly anticipated being accepted or rejected by "mean" (likely to reject) and "nice" (likely to accept) virtual peer confederates. Beta-series analyses revealed that the bilateral amygdala showed evidence of habituation to repeated social threat by the "mean" peer across groups. However, girls with MDD showed attenuated habituation in the right amygdala when anticipating feedback from the "mean" peers. Amygdala habituation was present (though attenuated) when anticipating social feedback from the "nice" peers, but did not vary by depression group. Findings identify a failure to habituate to anticipated social threat in MDD, suggesting altered social learning at the neural level. Attending to the dynamics of changing neural responses to anticipated social feedback may provide deeper insights into alterations in social and affective learning processes relevant to developing depression in adolescence.