Abstract/Details

Prefrontal cortex subregions and their involvement in the acquisition and extinction of conditioned fear


1997 1997

Other formats: Order a copy

Abstract (summary)

The prefrontal cortex (PFC) has been implicated in emotional processes in both humans and in rats. The exact role it plays and the contributions of its various subregions have not been well defined. Four studies were conducted to assess the role of rat PFC subregions in the acquisition and extinction of fear conditioned to contextual stimuli and to an explicit conditioned stimulus (CS). In the first two studies, lesions of ventral medial PFC (mPFCv) resulted only in prolonged responding to the CS during extinction, while lesions to the dorsal portion (mPFCd) resulted in increased freezing to both the context and CS during both acquisition and extinction. In the third study, lesions of the ventrolateral PFC resulted only in reduced contextual conditioning. In the final study, post-training lesions of mPFCv reduced contextual conditioning and eliminated the original (study 1) prolonged extinction effect. They further facilitated re-learning of the same task, and prolonged responding during re-extinction beyond the level expected from the amount of facilitation in relearning. As a whole, these results suggest a functional heterogeneity within rat PFC. They further suggest that mPFCv plays a role in the extinction of conditioned fear somewhat independent of initial fear levels, and may do so by being involved in the inhibition of conditioned responding when the response is no longer appropriate.

Indexing (details)


Subject
Physiological psychology;
Neurology;
Behaviorial sciences
Classification
0989: Physiological psychology
0317: Neurology
0384: Behaviorial sciences
Identifier / keyword
Psychology; Biological sciences
Title
Prefrontal cortex subregions and their involvement in the acquisition and extinction of conditioned fear
Author
Morgan, Maria Abell
Number of pages
218
Publication year
1997
Degree date
1997
School code
0146
Source
DAI-B 58/01, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
ISBN
9780591259735, 0591259737
Advisor
LeDoux, Joseph E.
University/institution
New York University
University location
United States -- New York
Degree
Ph.D.
Source type
Dissertations & Theses
Language
English
Document type
Dissertation/Thesis
Dissertation/thesis number
9717778
ProQuest document ID
304390692
Copyright
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
http://search.proquest.com/docview/304390692
Access the complete full text

You can get the full text of this document if it is part of your institution's ProQuest subscription.

Try one of the following:

  • Connect to ProQuest through your library network and search for the document from there.
  • Request the document from your library.
  • Go to the ProQuest login page and enter a ProQuest or My Research username / password.