Effects of halo pendol oit Me perforrmance of a response conditíoned under a fixed-interval schedule

Abstract

The performonce of an instrumental response, maintained under o fixed-interval schedule, was studied 30 sec., 40 min., 4 hr. and 8 hs.. afterr administering holoperidol, in rats. A marked reduction of operant responding was seen after the first two periods, and a behavioral recovery, of about 50% of control response rates, during the last two periods. A marked decrement in food and water intake was olso seen after the first three períods, and a near-normal intake 8 hr. after the treatment It is known that the adminis­tration of kaloperidol produces a specific and signiflcant reductton of acetylcitoline levels in tite caudate nucleus. Token togetiter, these data give fitrther support to the hypotitesis 

The performance of instrumental tasks is critically dependent upon the cholinergic activi­ty of the caudate nucleus.