Within-subject partial reinforcement extinction effect in autoshaping

Three autoshaping experiments explored the extinction of various keylight s timuli conditioned with partial and continuous reinforcement within the sam e pigeon subjects. Extinction of autoshaped keypecking proceeded more slowl y in a stimulus trained with 50% (Experiment 1) and 25% (Experiment 2) rein forcement compared with a stimulus given 100% reinforcement. Experiment 3 f ound conditioning with 75% reinforcement to generate more rapid extinction than chat with 25% reinforcement. These results have both theoretical and m ethodological implications for the study of extinction.