Neural systems for the expression of hypoalgesia during nonassociative fear. Behav Neurosci 1996 Aug;110(4):727-36
Date
08/01/1996Pubmed ID
8864264DOI
10.1037//0735-7044.110.4.727Scopus ID
2-s2.0-0029786448 (requires institutional sign-in at Scopus site) 68 CitationsAbstract
A single brief exposure to moderately intense while noise is sufficient to produce opioid-mediated antinociception in rats. This form of stress-induced hypoalgesia represents a response to unconditional fear or anxiety. Three experiments compared the neural circuits responsible for learned versus unlearned fear responses. Male rats received lesions of the medial geniculate nucleus, lateral or central nuclei of the amygdala, or the ventral, dorsal lateral, or dorsal medial periaqueductal gray (PAG). Controls showed a pronounced elevation in tail-flick latency following presentation of 90-dB white noise. All lesions, with the exception of dorsolateral and dorsomedial PAG, significantly blocked this response. These results support the idea that hypoalgesia produced by aversive auditory stimuli uses a common neural circuit regardless of whether the response is a product of associative learning or unconditional fear/anxiety.
Author List
Bellgowan PS, Helmstetter FJAuthor
Fred Helmstetter PhD Professor in the Psychology / Neuroscience department at University of Wisconsin - MilwaukeeMESH terms used to index this publication - Major topics in bold
AmygdalaAnimals
Association Learning
Brain
Brain Mapping
Fear
Geniculate Bodies
Male
Nerve Net
Nociceptors
Opioid Peptides
Pain Threshold
Periaqueductal Gray
Rats
Reaction Time
Thermosensing
