Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning

Frontiers in Cellular Neuroscience

Cellular Neuroscience

Megha Sehgal¹  Vanessa E. Ehlers¹  James R. Moyer² 

[1] Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States;Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States;Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, United States;

关键词: intrinsic excitability;    fear learning;    lateral amygdala;    synaptic plasticity;    spike frequency adaptation;   

DOI  :  10.3389/fncel.2023.1221176

 received in 2023-05-11, accepted in 2023-09-20,  发布年份 2023

来源: Frontiers

【 摘 要 】

IntroductionNew learning results in modulation of intrinsic plasticity in the underlying brain regions. Such changes in intrinsic plasticity can influence allocation and encoding of future memories such that new memories encoded during the period of enhanced excitability are linked to the original memory. The temporal window during which the two memories interact depends upon the time course of intrinsic plasticity following new learning.MethodsUsing the well-characterized lateral amygdala-dependent auditory fear conditioning as a behavioral paradigm, we investigated the time course of changes in intrinsic excitability within lateral amygdala neurons.ResultsWe found transient changes in the intrinsic excitability of amygdala neurons. Neuronal excitability was increased immediately following fear conditioning and persisted for up to 4 days post-learning but was back to naïve levels 10 days following fear conditioning. We also determined the relationship between learning-induced intrinsic and synaptic plasticity. Synaptic plasticity following fear conditioning was evident for up to 24 h but not 4 days later. Importantly, we demonstrated that the enhanced neuronal intrinsic excitability was evident in many of the same neurons that had undergone synaptic plasticity immediately following fear conditioning. Interestingly, such a correlation between synaptic and intrinsic plasticity following fear conditioning was no longer present 24 h post-learning.DiscussionThese data demonstrate that intrinsic and synaptic changes following fear conditioning are transient and co-localized to the same neurons. Since intrinsic plasticity following fear conditioning is an important determinant for the allocation and consolidation of future amygdala-dependent memories, these findings establish a time course during which fear memories may influence each other.

【 授权许可】

Unknown   
Copyright © 2023 Sehgal, Ehlers and Moyer.