Cargando…

Behavioral tagging in infant rats

Recent studies have shown that exposure to a novel environment may stabilize the persistence of weak memories, a phenomenon often attributed to a process referred to as “behavioral tagging.” While this phenomenon has been repeatedly demonstrated in adult animals, no studies to date have examined whe...

Descripción completa

Detalles Bibliográficos
Autores principales: Bae, Sarah E., Richardson, Rick
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Cold Spring Harbor Laboratory Press 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6191016/
https://www.ncbi.nlm.nih.gov/pubmed/30322891
http://dx.doi.org/10.1101/lm.047605.118
_version_ 1783363652722622464
author Bae, Sarah E.
Richardson, Rick
author_facet Bae, Sarah E.
Richardson, Rick
author_sort Bae, Sarah E.
collection PubMed
description Recent studies have shown that exposure to a novel environment may stabilize the persistence of weak memories, a phenomenon often attributed to a process referred to as “behavioral tagging.” While this phenomenon has been repeatedly demonstrated in adult animals, no studies to date have examined whether it occurs in infant animals, which is surprising given that infants exhibit an impaired ability to form long-term memories (LTMs). In the present study, infant (i.e., postnatal day (P) 17) rats were placed in a context and repeatedly shocked. Infant rats given brief open field exposure 1 h, but not 2 h, prior to conditioning exhibited enhanced retention when tested 1 d later (Experiments 1 and 2), but comparable retention when tested shortly after training (Experiment 2). Thus, exploration of an open field facilitates subsequent context fear memories by enhancing the persistence of the memory rather than strengthening the context-shock association at encoding. While exploration of an open field did not lead to better memory when animals were tested 3 d later (Experiment 3), a brief pretest shock led to a more pronounced reinstatement effect in rats exposed to the open field 1 h before conditioning (Experiment 4). Finally, unlike what has been reported in adults, Experiments 5 and 6 suggest that familiarization of the open field before subsequent exposure does not abolish the behavioral tagging effect in infants. Overall, while these findings suggest that similar behavioral tagging mechanisms to those reported in adults might be involved in the formation of LTMs in infant rats, they also suggest that there may be developmental differences in the retention of familiarization experiences.
format Online
Article
Text
id pubmed-6191016
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher Cold Spring Harbor Laboratory Press
record_format MEDLINE/PubMed
spelling pubmed-61910162019-11-01 Behavioral tagging in infant rats Bae, Sarah E. Richardson, Rick Learn Mem Research Recent studies have shown that exposure to a novel environment may stabilize the persistence of weak memories, a phenomenon often attributed to a process referred to as “behavioral tagging.” While this phenomenon has been repeatedly demonstrated in adult animals, no studies to date have examined whether it occurs in infant animals, which is surprising given that infants exhibit an impaired ability to form long-term memories (LTMs). In the present study, infant (i.e., postnatal day (P) 17) rats were placed in a context and repeatedly shocked. Infant rats given brief open field exposure 1 h, but not 2 h, prior to conditioning exhibited enhanced retention when tested 1 d later (Experiments 1 and 2), but comparable retention when tested shortly after training (Experiment 2). Thus, exploration of an open field facilitates subsequent context fear memories by enhancing the persistence of the memory rather than strengthening the context-shock association at encoding. While exploration of an open field did not lead to better memory when animals were tested 3 d later (Experiment 3), a brief pretest shock led to a more pronounced reinstatement effect in rats exposed to the open field 1 h before conditioning (Experiment 4). Finally, unlike what has been reported in adults, Experiments 5 and 6 suggest that familiarization of the open field before subsequent exposure does not abolish the behavioral tagging effect in infants. Overall, while these findings suggest that similar behavioral tagging mechanisms to those reported in adults might be involved in the formation of LTMs in infant rats, they also suggest that there may be developmental differences in the retention of familiarization experiences. Cold Spring Harbor Laboratory Press 2018-11 /pmc/articles/PMC6191016/ /pubmed/30322891 http://dx.doi.org/10.1101/lm.047605.118 Text en © 2018 Bae and Richardson; Published by Cold Spring Harbor Laboratory Press http://creativecommons.org/licenses/by-nc/4.0/ This article is distributed exclusively by Cold Spring Harbor Laboratory Press for the first 12 months after the full-issue publication date (see http://learnmem.cshlp.org/site/misc/terms.xhtml). After 12 months, it is available under a Creative Commons License (Attribution-NonCommercial 4.0 International), as described at http://creativecommons.org/licenses/by-nc/4.0/.
spellingShingle Research
Bae, Sarah E.
Richardson, Rick
Behavioral tagging in infant rats
title Behavioral tagging in infant rats
title_full Behavioral tagging in infant rats
title_fullStr Behavioral tagging in infant rats
title_full_unstemmed Behavioral tagging in infant rats
title_short Behavioral tagging in infant rats
title_sort behavioral tagging in infant rats
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6191016/
https://www.ncbi.nlm.nih.gov/pubmed/30322891
http://dx.doi.org/10.1101/lm.047605.118
work_keys_str_mv AT baesarahe behavioraltaggingininfantrats
AT richardsonrick behavioraltaggingininfantrats