Abstract
An experiment is described which uses various inferential post-conditioning revaluation techniques in order to clarify the associative substructure underlying Pavlovian electrodermal conditioning in human subjects. This study established a second-order skin conductance response (SCR) by pairing a CS1 with an aversive 115 dB tone (UCS), and then pairing a different stimulus (CS2) with CS1. The second-order SCR survived post-conditioning extinction of the response to CS1, but was abolished when (i) a post-conditioning habituation procedure resulted in a favourable revaluation of the tone UCS, or (ii) when subjects were given instructions which informed them that there would be no more UCS presentations. These results suggest that in the second-order electrodermal conditioning paradigm described, CR2 is not mediated by S-R links–-as it appears to be in second-order aversive conditioning in nonhuman animals–-but is affected by manipulations which modify the subject's cognitions concerning the UCS.
