Heightened neural activity and functional connectivity responses to social rejection in female adolescents at risk for depression: Testing the Social Signal Transduction Theory of Depression.

Background: Although social rejection is among the strongest proximal precipitants of major depressive disorder (MDD), little is known about the underlying neurobiological mechanisms and whether neural sensitivity to social rejection may help explain differences in MDD risk. To address this issue, we tested whether neural responses to social threat differed in female adolescents at high vs. low maternal risk for MDD.

Method: Female adolescents with (high-risk; n = 22, M = 14.68) and without (low-risk; n = 30, M = 15.07) a maternal history of depression were experimentally exposed to negative and neutral social evaluation while undergoing an fMRI scan. Neural responses were assessed by event-related activity and functional connectivity, as well as multivoxel pattern analysis. Activity and functional connectivity analyses focused on a priori-selected regions of interest implicated in self-referential processing and emotion regulation.

Results: Compared to low-risk female adolescents, high-risk female adolescents exhibited greater increases in self-reported depression and social disconnection following social evaluation. Moreover, compared to low-risk female adolescents, high-risk female adolescents exhibited greater amygdala responses to negative social evaluation and a differential pattern of functional connectivity in brain regions related to emotion regulation, self-referential processing, and negative affect. Additionally, these markers of neural threat reactivity were related to depressive symptoms.

Limitations: A cross-sectional study design and relatively small, Western sample.

Conclusions: These results suggest that exaggerated neural reactivity to social threat-and an atypical pattern of related functional connectivity-is evident in individuals with a preclinical risk factor for depression. Targeting such responding may thus be a fruitful strategy for preventing depression in at-risk youth.