Effects of Chlorpromazine on Rats' Acquisition of Lever-Press Responding with Immediate and Delayed Reinforcement
Date of Award
Master of Arts
Dr. Alan D. Poling
Dr. Lisa Baker
Dr. Jack Michael
Masters Thesis-Campus Only
The effects of chlorpromazine (0, 2, 6 and 10 mg/kg) on the acquisition of lever-press responding by rats were examined under conditions where reinforcement (food delivery) was immediate or delayed. Under the immediate reinforcement condition, water-deprived rats were exposed during 8-hr sessions to a fixed-ratio 1 schedule of food delivery without prior autoshaping or hand shaping. Under the delayed reinforcement condition, similar rats were exposed to a tandem fixed-ratio 1 fixed-time 8-s schedule of food delivery. Squads of eight rats were exposed to each delay condition and drug dose. For all subjects, responses on one lever produced food and responses on a second lever had no programmed consequences. Regardless of whether reinforcement was immediate or delayed , chlorpromazine reduced in dose-dependent fashion the mean number of operative-lever responses emitted, which suggests that the drug interfered with learning. Nonetheless, at all chlorpromazine doses except l 0 mg/kg, substantially more operative-lever than inoperative-lever responding occurred, indicating that the operant response was acquired. At 10 mg/kg, most subjects did not acquire lever-pressing regardless of whether they were exposed to the immediate or delayed reinforcement procedure.
Byrne, Thomas Peter, "Effects of Chlorpromazine on Rats' Acquisition of Lever-Press Responding with Immediate and Delayed Reinforcement" (1996). Masters Theses. 3569.