Conditioned Suppression With Different Aversive Stimuli: Electric Shock and Hot Air Blast

Abstract

In order to test the generality of the phenomenon of conditioned suppression, we used and compared two types of aversive stimuli: Electric Shock (EC) and Hot Air Blast (HAB). Four albino rats were divided into pairs and each pair was exposed to pairings of sound + EC or sound + HAB. The operant responding registered in this phase was bar-pressing (maintained in a variable interval schedule). Both subjects exposed to EC showed conditioned suppression of bar-pressing, whereas only one subject using the HAB pairing had the same effect. The suppression was partial with HAB, while with EC it was total. It was also noted that besides the suppression of operant responding, subjects which underwent the procedure with EC had a decrease in the frequency of exploratory responses. But, with the HAB, despite the bar-pressing suppression, it was observed an increase in the frequency of exploratory responses. These differences are discussed in what concerns to the nature of the aversive stimuli and the procedures adopted.