Maternal Overprotection in Childhood is Associated with Amygdala Reactivity and Structural Connectivity in Adulthood

Abstract

Recently, we reported that variability in early-life caregiving experiences maps onto individual differences in threat-related brain function. Specifically, we found that greater familial affective responsiveness is associated with increased amygdala reactivity to interpersonal threat, particularly in adolescents having experienced relatively low recent stress. Here, we conceptually replicate and extend on our previous work to provide further evidence that subtle variability in specific features of early caregiving shapes structural and functional connectivity between the amygdala and medial prefrontal cortex (mPFC) in a cohort of 312 young adult volunteers. Multiple regression analyses revealed that participants who reported higher maternal but not paternal protection exhibited increased amygdala reactivity to explicit signals of interpersonal threat (i.e., angry facial expressions) but not implicit signals of broad environmental threat (i.e., fearful facial expressions). While amygdala functional connectivity with regulatory regions of the mPFC was not significantly associated with maternal protection, participants who reported higher maternal protection exhibited relatively decreased structural integrity of the uncinate fasciculus (UF), a white matter tract connecting these same brain regions. The observed associations were independent of the potential confounding influences of participant sex, socioeconomic status, and self-reported childhood trauma. There were no significant associations between structural or functional brain measures and either maternal or paternal care ratings. These findings suggest that an over controlling parenting style in mothers during childhood is associated with functional and structural alterations of brain regions involved in generating and regulating responses to threat in young adulthood.