CHILDHOOD MALTREATMENT AND NEUROBIOLOGICAL VULNERABILITY TO DEPRESSION: A REVIEW

Numerous studies suggest that child abuse and neglect significantly increase risk for depression. Major depressive disorder (MDD) is a highly recurrent disorder. This high rate of recurrence of depressive episodes probably reflects the presence of stable vulnerability factors: among the strongest risk factors for developing MDD are experiences of childhood maltreatment. Every year in the U.S. over 500,000 cases of physical and sexual abuse are documented. Despite the widely appreciated magnitude of the problem, the precise mechanism by which childhood trauma may increase the risk for depression remains unclear. Research comparing depressed individuals with and without a history of early life trauma suggests important differences on several key neurobiological features including endocrine and autonomic activity, as well as on region-specific brain morphology. This evidence suggests that brain morphology and physiology are influenced by both heritable and stress-induced influences, which have been observed in both human and animal models. In this context, cognitive models of depression propose that biased processing of emotional material is a stable vulnerability factor that affects the onset, maintenance, and recurrence of depressive episodes. Cognitive biases can be observed in depressed and abused participants: these impairments may underlie reduced affect regulation and social interaction, and therefore contribute to the development and maintenance of such disorder.