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Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions

Norepinephrine is released in the amygdala following negatively arousing learning conditions. This event initiates a cascade of changes including the transcription of activity-regulated cytoskeleton-associated protein (Arc) expression, an early-immediate gene associated with memory encoding. Recent...

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Autores principales: Young, Erica J., Williams, Cedric L.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3852216/
https://www.ncbi.nlm.nih.gov/pubmed/24367308
http://dx.doi.org/10.3389/fnbeh.2013.00191
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author Young, Erica J.
Williams, Cedric L.
author_facet Young, Erica J.
Williams, Cedric L.
author_sort Young, Erica J.
collection PubMed
description Norepinephrine is released in the amygdala following negatively arousing learning conditions. This event initiates a cascade of changes including the transcription of activity-regulated cytoskeleton-associated protein (Arc) expression, an early-immediate gene associated with memory encoding. Recent evidence suggests that the valence of emotionally laden encounters may generate lateralized, as opposed to symmetric release of this transmitter in the right or left amygdala. It is currently not clear if valence-induced patterns of selective norepinephrine output across hemispheres are also reproduced in downstream pathways of cellular signaling necessary for memory formation. This question was addressed by determining if Arc expression is differentially distributed across the right and left amygdala following exposure to positively or negatively valenced learning conditions respectively. Male Sprague Dawley rats were randomly assigned to groups exposed to the Homecage only, five auditory tones only, or five auditory tones paired with footshock (0.35 mA) during Pavlovian fear conditioning. Western blot analysis revealed that Arc expression in the right amygdala was elevated significantly above that observed in the left amygdala 60 and 90 min following fear conditioning. Similarly, subjects exposed to a negatively valenced outcome consisting of an unexpected reduction in food rewards showed a greater level of Arc expression in only the right, but not left basolateral amygdala. Presenting a positively valenced event involving an unexpected increase in food reward magnitude following bar pressing, resulted in significantly greater Arc expression in the left, but not right basolateral amygdala (p < 0.01). These findings indicate that the valence of emotionally arousing learning conditions is reflected at later stages of synaptic plasticity involving the transcription of immediate early genes such as Arc.
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spelling pubmed-38522162013-12-23 Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions Young, Erica J. Williams, Cedric L. Front Behav Neurosci Neuroscience Norepinephrine is released in the amygdala following negatively arousing learning conditions. This event initiates a cascade of changes including the transcription of activity-regulated cytoskeleton-associated protein (Arc) expression, an early-immediate gene associated with memory encoding. Recent evidence suggests that the valence of emotionally laden encounters may generate lateralized, as opposed to symmetric release of this transmitter in the right or left amygdala. It is currently not clear if valence-induced patterns of selective norepinephrine output across hemispheres are also reproduced in downstream pathways of cellular signaling necessary for memory formation. This question was addressed by determining if Arc expression is differentially distributed across the right and left amygdala following exposure to positively or negatively valenced learning conditions respectively. Male Sprague Dawley rats were randomly assigned to groups exposed to the Homecage only, five auditory tones only, or five auditory tones paired with footshock (0.35 mA) during Pavlovian fear conditioning. Western blot analysis revealed that Arc expression in the right amygdala was elevated significantly above that observed in the left amygdala 60 and 90 min following fear conditioning. Similarly, subjects exposed to a negatively valenced outcome consisting of an unexpected reduction in food rewards showed a greater level of Arc expression in only the right, but not left basolateral amygdala. Presenting a positively valenced event involving an unexpected increase in food reward magnitude following bar pressing, resulted in significantly greater Arc expression in the left, but not right basolateral amygdala (p < 0.01). These findings indicate that the valence of emotionally arousing learning conditions is reflected at later stages of synaptic plasticity involving the transcription of immediate early genes such as Arc. Frontiers Media S.A. 2013-12-05 /pmc/articles/PMC3852216/ /pubmed/24367308 http://dx.doi.org/10.3389/fnbeh.2013.00191 Text en Copyright © 2013 Young and Williams. http://creativecommons.org/licenses/by/3.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Neuroscience
Young, Erica J.
Williams, Cedric L.
Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions
title Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions
title_full Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions
title_fullStr Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions
title_full_unstemmed Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions
title_short Differential activation of amygdala Arc expression by positive and negatively valenced emotional learning conditions
title_sort differential activation of amygdala arc expression by positive and negatively valenced emotional learning conditions
topic Neuroscience
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3852216/
https://www.ncbi.nlm.nih.gov/pubmed/24367308
http://dx.doi.org/10.3389/fnbeh.2013.00191
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