Brain connectivity mediates the association between childhood maltreatment and personality in young adults

Childhood maltreatment (CM) is widely acknowledged to have a lasting impact on mental health. However, the neurobiological underpinnings of CM and its long-term effects on personality remain unclear. This study aims to identify the functional connectivity (FC) basis of CM through a data-driven analytic strategy, and to examine the association among CM, FC, and personality. A total of 332 young adults (aged 17-24 years) with resting functional magnetic resonance imaging scans were included. CM level was assessed using the Childhood Trauma Questionnaire and personality was measured with the Temperament and Character Inventory. Multivariate distance matrix regression (MDMR) was performed to identify key regions where inter-individual FC variations were linked to CM at the voxel level, and a follow-up seed-based FC analysis was conducted to elucidate specific connectivity patterns of these key regions. MDMR identified four regions in the inferior parietal lobule (IPL), calcarine sulcus (CAL), middle occipital gyrus, and middle temporal gyrus. Specifically, follow-up analysis showed that the FC between IPL and sensorimotor network/theory of mind network, and between CAL and salience network were negatively associated with CM. Moreover, CM was negatively associated with reward dependence and cooperativeness, and those identified FCs mediated the relationship between CM and cooperativeness. Our results emphasize that CM has an enduring influence on the integration of sensory and social-cognitive processing, revealing the neurobiological consequences of CM and providing a new framework for understanding how CM leads to maladaptive personality.