Previous institutionalization is associated with elevated functional connectivity between the nucleus accumbens and amygdala during aversive learning

Institutionalization is a profound form of early adversity that is associated with increased risk for internalizing disorders, which most commonly have their onset during adolescence. Developmental models emphasize how differences in childhood learning contribute to avoidance behaviors, a core pathway linking adversity to internalizing disorders. Yet, little empirical research has tested this theory. 43 previously institutionalized (PI; 12.1-22.8 years) and 47 comparison (9.9-22.9 years) youth completed an aversive learning task while undergoing fMRI. The task involved an escapable stimulus reinforced with an aversive sound (CS+_r), the same stimulus without reinforcement (CS+_nr), and an escapable stimulus that was never reinforced (CS-). Internalizing symptoms were measured using the parent-report Revised Child Anxiety and Depression Scales. Functional connectivity between the nucleus accumbens (NAcc) and amygdala was elevated among the PI versus comparison youth across stimuli (p = .036). Exploratory analyses found that NAcc-amygdala connectivity was elevated among the PI youth during early adolescence relative to late adolescence (p = .009). Institutionalization may impact neurodevelopment in ways that increase responsiveness of threat neurocircuitry across threatening and safe stimuli. Differences in NAcc-amygdala functional connectivity may attenuate with age following adoption.