条件性恐惧的大脑回路研究概述

近年来 ,条件性恐惧的研究表明 :杏仁核是大脑中参与恐惧记忆获得、贮存和表达的一个重要组成部分 ;听觉条件性恐惧的神经回路是条件刺激和无条件刺激传递到杏仁核 ,在杏仁核中运行 ,并将这些信息投射到脑干控制系统 ,控制恐惧反应 ;条件性恐惧具有可塑性 ,杏仁核中的外侧神经核是可塑性的中枢部位 ,参与其可塑性的神经递质是N 甲基 D 天冬氨酸受体 ;恐惧情感的产生可能是前额叶皮层、海马和杏仁核三个脑区共同激活的结果。     

Self-reported neglect,amygdala volume,and symptoms of anxiety in adolescent boys

Experiences of psychosocial neglect affect the developing brain and may place individuals at increased risk for anxiety. The majority of research in this area has focused on children who have experienced severe psychosocial deprivation; it is not clear whether typical variation in neglect experienced in community samples would have the same neurobiological consequences as those documented in extreme samples. The present study examined the associations among self-reported childhood neglect, amygdala volume, and anxiety symptoms in a community sample of 138 adolescents ages 9–15 years (43% male). Linear mixed modeling yielded a three-way interaction of neglect, sex, and brain hemisphere, reflecting a significant positive association between neglect and right amygdala volume in boys. Additional analyses indicated that right amygdala volume significantly mediated the association between neglect and anxiety symptoms in boys. These findings are consistent with previous reports of larger amygdala volumes in previously institutionalized children, and with documented associations between caregiving deprivation and anxiety symptoms. The results suggest that the effects of childhood neglect on limbic structures are sex-specific and lateralized, and provide support for a neural mechanism relating childhood neglect to later difficulties in emotional functioning.