Olfactory learning and memory impairments following lesions to the hippocampus and perirhinal-entorhinal cortex.
The role of the hippocampus and perirhinal-entorhinal cortex was examined in an olfactory discrimination paradigm. Small neurotoxic lesions of the hippocampus (21% tissue damage) yielded relatively unimpaired olfactory retention across brief (30 s), intermediate (approximately 5 min), and 24-hr delays, whereas impairments were noted at 5-day retention intervals. Larger hippocampal lesions (63% tissue damage) spared memory at intermediate delays, with no impact at 8-day retention intervals. Aspiration lesions directed at the perirhinal-entorhinal cortex produced a variable performance pattern, with impairments noted at intermediate, 24-hr, and 5-day delays. Results suggest the hippocampus is not specifically involved in retaining olfactory information, with additional consideration given to the relationship between lesion size and memory impairment.
Kaut
Kevin P
KP
Department of Psychology, University of Akron, Ohio 44325-4301, USA. kpk@uakron.edu
Bunsey
Michael D
MD
Riccio
David C
DC
D000818:Animals; D001522:Behavior, Animal; D001931:Brain Mapping; D004193:Discrimination Learning; D018728:Entorhinal Cortex / Q000293:injuries / Q000503:physiopathology*; D006624:Hippocampus / Q000293:injuries / Q000503:physiopathology*; D008297:Male; D008569:Memory Disorders / Q000503:physiopathology*; D008570:Memory, Short-Term; D011597:Psychomotor Performance; D051381:Rats; D020318:Rats, Long-Evans; D012153:Retention, Psychology / Q000502:physiology*; D012903:Smell