Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1995-10-10
pubmed:abstractText
Cholinergic antagonism impacts selected learning tasks. To understand where scopolamine exerts its action, learning tasks differentially sensitive to hippocampus and amygdala lesions were used. Hippocampal lesions prevent context fear conditioning without effect on tone conditioning. These lesions also produce a time-dependent retrograde deficit in context conditioning. The amygdala is necessary for both tone and context conditioning. To examine the possibility that cholinergic antagonism mimics hippocampal damage or amygdala damage, rats were given scopolamine (1 mg/kg) either before or after fear conditioning. In the fear conditioning procedure, rats received tone-footshock or context-footshock pairings. Evidence of conditioning to the tone and the context was provided by observation of freezing. When given prior to training, scopolamine blocked fear conditioning to the tone in a dose-dependent fashion but had no effect on context conditioning. The impairment of tone conditioning did not occur with methylscopolamine, indicating the central action of the drug. Rats given scopolamine immediately following fear conditioning, tested later in a drug-free state, froze more to the tone than rats given a control injection. The effect of scopolamine on freezing to the context was not reliable. The present results suggest that scopolamine's impact on fear conditioning is mediated by some mechanism other than impaired hippocampal or amygdala functioning.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1074-7427
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
174-80
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:7663891-Acoustic Stimulation, pubmed-meshheading:7663891-Amygdala, pubmed-meshheading:7663891-Animals, pubmed-meshheading:7663891-Arousal, pubmed-meshheading:7663891-Association Learning, pubmed-meshheading:7663891-Brain, pubmed-meshheading:7663891-Cholinergic Fibers, pubmed-meshheading:7663891-Conditioning, Classical, pubmed-meshheading:7663891-Discrimination Learning, pubmed-meshheading:7663891-Dose-Response Relationship, Drug, pubmed-meshheading:7663891-Electroshock, pubmed-meshheading:7663891-Fear, pubmed-meshheading:7663891-Hippocampus, pubmed-meshheading:7663891-Long-Term Potentiation, pubmed-meshheading:7663891-Male, pubmed-meshheading:7663891-Mental Recall, pubmed-meshheading:7663891-N-Methylscopolamine, pubmed-meshheading:7663891-Parasympatholytics, pubmed-meshheading:7663891-Rats, pubmed-meshheading:7663891-Retention (Psychology), pubmed-meshheading:7663891-Scopolamine Derivatives, pubmed-meshheading:7663891-Scopolamine Hydrobromide, pubmed-meshheading:7663891-Social Environment
pubmed:year
1995
pubmed:articleTitle
Scopolamine impairs acquisition and facilitates consolidation of fear conditioning: differential effects for tone vs context conditioning.
pubmed:affiliation
Department of Psychology, University of California, Los Angeles 90024, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.