Factors influencing active avoidance behavior in rats with ventromedial hypothalamic lesions

Content Provider	Semantic Scholar
Author	King, Bruce M. Alheid, George F. Grossman, Sebastian P.
Copyright Year	1977
Abstract	Abstract Ventromedial hypothalamic lesioned rats maintained at preoperative body weight received an equal number of shocks while emitting significantly fewer responses than controls in a lever-pressing free-operant avoidance paradigm, and performed as well as unoperated animals in lever-pressing and shuttle box (both 1- and 2-way) discriminated avoidance tasks. The failure of VMH lesions to facilitate performance in the 2-way avoidance paradigm was probably the result of a ceiling effect. With the exception of the simple one-way avoidance task, obese lesioned rats were markedly impaired in the acquisition of all active avoidance behavior, but escape behavior was not affected. When tested in a free-operant paradigm, the avoidance performance of well trained lesioned animals varied inversely with body weight. As obese rats displayed lower flinch thresholds to shock than controls and similar levels of activity and responding as lean lesioned animals, it was concluded that their impaired avoidance behavior was not due to changes in sensitivity or mobility. The possible relation to other VMH lesion- and/or obesity-induced deficits is discussed.
Starting Page	901
Ending Page	913
Page Count	13
File Format	PDF HTM / HTML
DOI	10.1016/0031-9384(77)90200-1
PubMed reference number	905399
Journal	Medline
Volume Number	18
Alternate Webpage(s)	https://api.elsevier.com/content/article/pii/0031938477902001
Alternate Webpage(s)	https://www.sciencedirect.com/science/article/pii/0031938477902001?dgcid=api_sd_search-api-endpoint
Alternate Webpage(s)	https://doi.org/10.1016/0031-9384%2877%2990200-1
Journal	Physiology & Behavior
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article