The discriminative stimulus effects of cocaine in a pavlovian sexual approach paradigm in male Japanese quail

Two groups of male Japanese quail (Coturnix japonica) to discriminate cocaine from saline in a conditioned approach procedure maintained by sexual reinforcement. For 1 group, cocaine (10 mg/kg ip) was administered prior to a conditioned stimulus (CS) that predicted copulation; saline followed by a CS predicted no copulation. A second group underwent the opposite training regimen. Results revealed apparent between-group differences in the rates of acquisition of the discrimination; however, during extinction trials, both groups responded more under the drug condition that predicted the female than to the condition that predicted no female. The results suggested that a drug discrimination may be maintained by sexual reinforcement. The findings are discussed with regard to interactions of cocaine and sexual reward, as well as to Pavlovian conditional stimulus control.