Behavioral and immunohistochemical characterization of rapid reconditioning following extinction of contextual fear.
Learn Mem
; 26(10): 1-16, 2019 10.
Article
em En
| MEDLINE
| ID: mdl-31527183
ABSTRACT
A fundamental property of extinction is that the behavior that is suppressed during extinction can be unmasked through a number of postextinction procedures. Of the commonly studied unmasking procedures (spontaneous recovery, reinstatement, contextual renewal, and rapid reacquisition), rapid reacquisition is the only approach that allows a direct comparison between the impact of a conditioning trial before or after extinction. Thus, it provides an opportunity to evaluate the ways in which extinction changes a subsequent learning experience. In five experiments, we investigate the behavioral and neurobiological mechanisms of postextinction reconditioning. We show that rapid reconditioning of unsignaled contextual fear after extinction in male Long-Evans rats is associative and not affected by the number or duration of extinction sessions that we examined. We then evaluate c-Fos expression and histone acetylation (H4K8) in the hippocampus, amygdala, prefrontal cortex, and bed nucleus of the stria terminalis. We find that in general, initial conditioning has a stronger impact on c-Fos expression and acetylation than does reconditioning after extinction. We discuss implications of these results for theories of extinction and the neurobiology of conditioning and extinction.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Núcleos Septais
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Comportamento Animal
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Proteínas Proto-Oncogênicas c-fos
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Córtex Pré-Frontal
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Condicionamento Psicológico
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Extinção Psicológica
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Medo
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Hipocampo
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Tonsila do Cerebelo
Limite:
Animals
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article