Amount of fear extinction changes its underlying mechanisms

eLife

Sukwoo Choi¹  Jihye Kim²  Kyungjoon Park³  Sukwoon Song³  Bobae An³  Sukwon Lee³ 

[1] Department of Neural Development and Disease, Korea Brain Research Institute, Daegu, Korea;Department of Neurobiology, Duke University, Durham, United States;School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul, Korea;

关键词: fear extinction;    lateral amygdala;    prefrontal cortex;    basal nucleus of amygdala;    amygdala intercalated neurons;   

DOI  :  10.7554/eLife.25224

来源: DOAJ

【 摘 要 】

There has been a longstanding debate on whether original fear memory is inhibited or erased after extinction. One possibility that reconciles this uncertainty is that the inhibition and erasure mechanisms are engaged in different phases (early or late) of extinction. In this study, using single-session extinction training and its repetition (multiple-session extinction training), we investigated the inhibition and erasure mechanisms in the prefrontal cortex and amygdala of rats, where neural circuits underlying extinction reside. The inhibition mechanism was prevalent with single-session extinction training but faded when single-session extinction training was repeated. In contrast, the erasure mechanism became prevalent when single-session extinction training was repeated. Moreover, ablating the intercalated neurons of amygdala, which are responsible for maintaining extinction-induced inhibition, was no longer effective in multiple-session extinction training. We propose that the inhibition mechanism operates primarily in the early phase of extinction training, and the erasure mechanism takes over after that.

【 授权许可】

Unknown