title: Inactivation of ventral hippocampus interfered with cued-fear acquisition but did not influence later recall or discrimination.
abstract: The ventral hippocampus (VH) is involved in the both the acquisition and recall of conditioned fear. Here, we tested the role of VH in acquisition and recall of a conditioned fear discrimination. Intra-VH vehicle or muscimol injections were made 1h prior to a CS+/CS- conditioning or prior to later recall. Vehicle treated rats exhibited discrimination with significantly greater freezing to the CS+ than to the CS- whereas muscimol treated rats did not freeze. Injections made before recall had no effect as both treatment groups displayed equal freezing in response to the CS+, and discrimination. While these results are consistent with several reports, the failure to influence fear discrimination upon recall appears to contrast with the hypothesized role of VH in recall of extinguished conditioned fear cues.
authors.affiliation: Department of Psychology, Boston College, Chestnut Hill, MA 02467 USA.
authors.forename: Veronica M
authors.initials: VM
authors.lastname: Chen
authors.affiliation: Department of Psychology, Boston College, Chestnut Hill, MA 02467 USA.
authors.forename: Allison R
authors.initials: AR
authors.lastname: Foilb
authors.affiliation: Department of Psychology, Boston College, Chestnut Hill, MA 02467 USA. Electronic address: j.christianson@bc.edu.
authors.forename: John P
authors.initials: JP
authors.lastname: Christianson
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003213:Conditioning, Psychological / Q000187:drug effects*; D003463:Cues; D004192:Discrimination, Psychological / Q000187:drug effects*; D005239:Fear / Q000187:drug effects*; D058785:GABA-A Receptor Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D011939:Mental Recall / Q000187:drug effects*; D009118:Muscimol / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D058785:GABA-A Receptor Agonists; D009118:Muscimol
keywords: Fear; Hippocampus; Muscimol; Rat; Safety; ptsd