Objective: Advances in our knowledge of mental disorder (MD) genetics have contributed to a better understanding of their pathophysiology. Nonetheless, several questions and doubts persist. Recent studies have focused on environmental influences in the development of MDs, and the advent of neuroscientific methodologies has provided new perspectives. Early life events, such as childhood stress, may affect neurodevelopment through mechanisms such as gene-environment interactions and epigenetic regulation, thus leading to diseases in adulthood. The aim of this paper is to review the evidence regarding the role of the environment, particularly childhood stress, in the pathophysiology of MD.
Methodology: We reviewed articles that evaluated environmental influences, with a particular focus on childhood trauma, brain morphology, cognitive functions, and the development of psychopathology and MD.
Results and conclusion: MRI studies have shown that exposure to trauma at an early age can result in several neurostructural changes, such as the reduction of the hippocampus and corpus callosum. Cognitive performance and functioning are also altered in this population. Finally, childhood stress is related to an increased risk of developing MD such as depression, bipolar disorder, schizophrenia and substance abuse. We conclude that there is robust evidence of the role of the environment, specifically adverse childhood experiences, in various aspects of MD.