[Neurobiological consequences of early life stressors]

Abstract

This article reviews the neurobiological effects of psychosocial stress. In the first part, the results of childhood traumas, neurobiological models which explain the effects of psychosocial stress and animal studies on this subject are introduced. In a number of studies, an increase in the adulthood prevalence of depression, anxiety disorders and other psychiatric disorders was shown in children who were exposed to early life stress. Pre-clinical and clinical studies have shown that early life stressors cause endocrine, autonomous and behavioral stress responses as a result of permanent sensitivity in corticotropin releasing factor and other neurotransmitter systems in the central nervous system. As a result of this sensitivity, repeating stressors may play an important role in the pathogenesis of depression, anxiety disorders and psychophysiologic disorders. In contrast with the numerous studies investigating the long term effects of early life stressors on the brain, there are very few studies investigating the acute effects of these stressors. In spite of these limitations, it is known that psychosocial stressors may cause different neurobiological results in adults and children. After reviewing the relationship between psychosocial stressors and the neurobiology of affective disorders, it is explained how psychosocial stresses cause sensitivities in the central nervous system and how these sensitivities cause illness. These interactions have implications for treatment in the light of the explained mechanisms. In the last part of the article, new treatment strategies developed for correcting the effects of stress on the central nervous system are introduced.