The reward-hypersensitivity model posits that trait reward hypersensitivity should elicit hyper/hypo-approach motivation following exposure to recent life events that activate (goal striving and goal attainment) or deactivate (goal failure) the reward system, respectively. To test these hypotheses, we had 87 young adults with high trait reward (HRew) sensitivity or moderate trait reward (MRew) sensitivity report frequency of life events via the Life Event Interview. Brain activation was assessed during the functional MRI monetary-incentive-delay task. Greater exposure to goal-striving events was associated with higher nucleus accumbens (NAc) reward anticipation among HRew participants and lower orbitofrontal cortex (OFC) reward anticipation among MRew participants. Greater exposure to goal-failure events was associated with higher NAc and OFC reward anticipation only among HRew participants. This study demonstrated different neural reward anticipation (but not outcome) following reward-relevant events for HRew individuals compared with MRew individuals. Trait reward sensitivity and reward-relevant life events may jointly modulate reward-related brain function, which has implications for understanding psychopathology.

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Early adversity confers risk for depression in part through its association with recent (i.e., proximal) acute stress. However, it remains unresolved whether: a) early adversity predicts increases in recent acute stress over time; b) all – or only certain types – of recent events mediate the relationship between early adversity and depression; and c) early adversity places individuals at greater risk for depression via greater exposure to independent (i.e., fateful) interpersonal events or via greater generation of dependent (i.e., partially self-initiated) interpersonal events (i.e., stress generation) or both. These questions were examined in a 3-wave longitudinal study of early adolescent girls (N = 125; M = 12.35 years [SD = .77]) with no history of diagnosable depression using contextual life stress and diagnostic interviews. Path analyses indicated that increases in past-year acute interpersonal, but not non-interpersonal, stress mediated the link between early adversity and depressive symptoms. The mediating role of interpersonal events was limited to independent ones, suggesting increases in interpersonal event exposure, not interpersonal stress generation, acted as a mediator. Finally, findings support prior evidence that early adversity may not directly predict future depressive symptoms. Implications for understanding the role of recent stress in the association between early adversity and adolescent depression are discussed.

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