Childhood assaultive trauma and physical aggression: Links with cortical thickness in prefrontal and occipital cortices

Abstract

Although the link between childhood maltreatment and violence perpetration in adulthood (i.e., the "cycle of violence") is well-documented, the neural mechanisms driving these processes remain relatively unknown. The objectives of this study were to investigate whether cortical thickness in adulthood varies as a function of childhood assaultive trauma exposure and whether such neurobiological markers of early trauma relate to the perpetration of aggression across the lifespan. In a sample of 138 ethnically-diverse men and women, whole-brain analysis of the cortical mantle revealed that individuals with exposure to assaultive trauma before age 13 had less cortical thickness in two clusters that survived multiple comparison correction: a region that peaked in the left lateral orbitofrontal cortex (OFC) and a region peaking in the right pericalcarine cortex. Diminished cortical thickness in the left OFC cluster was, in turn, associated with greater physical aggression, and mediation analysis revealed that reductions in cortical thickness in this left prefrontal region partially accounted for the association between exposure to childhood assaultive trauma and lifetime perpetration of aggression in adulthood. Findings extend previous investigations into the morphological correlates of early assaultive trauma by implicating reductions in cortical thickness as a potential mechanism linking early violence exposure to violence perpetration that extends into adulthood.

Keywords: Cycle of violence; Orbitofrontal cortex; Pericalcarine; Stress exposure.