Postresponse exposure to warning signal in avoidance extinction

Delayed termination of the warning signal following extinction responses has been shown to facilitate extinction of discriminative avoidance. In order to determine the relative roles in extinction of delayed termination per se and postresponse exposure to the warning signal, which is necessarily confounded with delayed termination treatment, seven groups of rats were first trained on a one-way avoidance task in which a buzzer served as part of the warning-signal complex. Then, on nonshock extinction trials, the buzzer (a) terminated immediately with a response and was not reinstated in the postresponse interval, (b) terminated immediately with a response and was reinstated for a 5- or 10-sec period 5 or 15 sec following the response, or (c) terminated 5 or 10 sec following a response (delayed termination). Results indicated that exposure to the buzzer at postresponse intervals greater than 5 sec following responses was critically involved in reducing resistance to extinction. This finding supports a conditioned relief interpretation of the delayed warning signal termination effect and is consistent with the effect of response prevention techniques on extinction.