Sex differences in learned fear expression and extinction involve altered gamma oscillations in medial prefrontal cortex

Fenton, G.E.; Halliday, D.M.; Mason, Rob; Bredy, Timothy W.; Stevenson, Carl W.

Abstract

Sex differences in learned fear expression and extinction involve the medial prefrontal cortex (mPFC). We recently demonstrated that enhanced learned fear expression during auditory fear extinction and its recall is linked to persistent theta activation in the prelimbic (PL) but not infralimbic (IL) cortex of female rats. Emerging evidence indicates that gamma oscillations in mPFC are also implicated in the expression and extinction of learned fear. Therefore we re-examined our in vivo electrophysiology data and found that females showed persistent PL gamma activation during extinction and a failure of IL gamma activation during extinction recall. Altered prefrontal gamma oscillations thus accompany sex differences in learned fear expression and its extinction. These findings are relevant for understanding the neural basis of post-traumatic stress disorder, which is more prevalent in women and involves impaired extinction and mPFC dysfunction.

Citation

Fenton, G., Halliday, D., Mason, R., Bredy, T. W., & Stevenson, C. W. (2016). Sex differences in learned fear expression and extinction involve altered gamma oscillations in medial prefrontal cortex. Neurobiology of Learning and Memory, 135, https://doi.org/10.1016/j.nlm.2016.06.019

• Journal Article Type: Article
• Acceptance Date: Jun 21, 2016
• Online Publication Date: Jun 21, 2016
• Publication Date: Nov 1, 2016
• Deposit Date: Sep 22, 2016
• Publicly Available Date: Sep 22, 2016
• Journal: Neurobiology of Learning and Memory
• Print ISSN: 1074-7427
• Electronic ISSN: 1095-9564
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 135
• DOI: https://doi.org/10.1016/j.nlm.2016.06.019
• Keywords: Sex differences; Fear conditioning; Extinction; Prelimbic; Infralimbic; Gamma oscillations
• Public URL: https://nottingham-repository.worktribe.com/output/974201
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S1074742716300934