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

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 m...

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Main Authors: Megha Sehgal, Vanessa E. Ehlers, James R. Moyer
Format: Article
Language:English
Published: Frontiers Media S.A. 2023-10-01
Series:Frontiers in Cellular Neuroscience
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fncel.2023.1221176/full
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author Megha Sehgal
Vanessa E. Ehlers
James R. Moyer
James R. Moyer
author_facet Megha Sehgal
Vanessa E. Ehlers
James R. Moyer
James R. Moyer
author_sort Megha Sehgal
collection DOAJ
description 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.
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spelling doaj.art-f0ce1e8f73d742738312cb9ff2b711bf2023-10-09T10:01:37ZengFrontiers Media S.A.Frontiers in Cellular Neuroscience1662-51022023-10-011710.3389/fncel.2023.12211761221176Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioningMegha Sehgal0Vanessa E. Ehlers1James R. Moyer2James R. Moyer3Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United StatesDepartment of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United StatesDepartment of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United StatesDepartment of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, United StatesIntroductionNew 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.https://www.frontiersin.org/articles/10.3389/fncel.2023.1221176/fullintrinsic excitabilityfear learninglateral amygdalasynaptic plasticityspike frequency adaptation
spellingShingle Megha Sehgal
Vanessa E. Ehlers
James R. Moyer
James R. Moyer
Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
Frontiers in Cellular Neuroscience
intrinsic excitability
fear learning
lateral amygdala
synaptic plasticity
spike frequency adaptation
title Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
title_full Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
title_fullStr Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
title_full_unstemmed Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
title_short Synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
title_sort synaptic and intrinsic plasticity within overlapping lateral amygdala ensembles following fear conditioning
topic intrinsic excitability
fear learning
lateral amygdala
synaptic plasticity
spike frequency adaptation
url https://www.frontiersin.org/articles/10.3389/fncel.2023.1221176/full
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AT jamesrmoyer synapticandintrinsicplasticitywithinoverlappinglateralamygdalaensemblesfollowingfearconditioning
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