Overtraining in classical conditioning: A comparison of motor and cardiac systems in dogs

Data from the analysis of the Overlearning Reversal Effect (ORE) noted in a simultaneous, visual discrimination task, and the lack of this effect in a position habit discrimination, led to the prediction that the ORE would not be noted in classical conditioning. It was further noted that very little work on discrimination learning had been reported in Pavlovian conditioning. The idea of schizokinesis, as observed by Gantt and others in classical conditioning, has been elaborated using the simple conditioning paradigm, and no data were available to test whether this same split would occur on a more complex level of conditioning, such as a discrimination task. To test these ideas, nine dogs were trained to a criterion of minimum discrimination, and then divided into three groups and given varying amounts of overtraining (OT). The discrimination task given the animal was to flex its paw during the CS+ signalling the onset of a brief shock. After the varying amounts of OT all groups were placed in extinction, followed by reversal training until each dog reached a criterion of minimum reversal. The results indicated 1) that the cardiac discrimination did not form before the motor discrimination; 2) extinction of differentiation was not significantly affected by the amount of OT given; 3) the mean level of responding in the motor system during extinction was highly correlated with the mean level of responding during the initial discrimination training; 4) OT had no effect on the speed of reversal of either the motor or the cardiac systems; 5) the speed of reversal learning in the motor system was highly correlated with the speed of initial discrimination.