RECOGNITION OF PROPIONIC-ACID VAPOR AFTER REMOVAL OF THE OLFACTORY-BULB AREA ASSOCIATED WITH HIGH 2-DG UPTAKE

Rats were trained in an olfactometer to recognize the odor of propioni c acid using a go, no-go operant discrimination tasks in which propion ic acid vapor served as the negative stimulus and a series of novel od ors served as positive stimuli. After training, rats readily responded to all novel odors but not to propionic acid. Removal of the olfactor y bulb region previously identified with 2-deoxyglucose (2-DG) as bein g responsive to propionic acid had no effect on recognition of propion ic acid, ability to discriminate novel odors from propionic acid or od or mixtures containing propionic acid or to discriminate propionic aci d from a very similar odor (acetic acid). These results demonstrate th at the 2-DG-identified propionic acid focal area is not essential for detection, discrimination or recognition of the odor. The outcomes are in accord with and extend those of other behavioral studies that have failed to demonstrate a functional correlate for the regional increas es in metabolic activity produced by exposure to specific odors.