Effects of Potentially Phobic Conditioned Stimuli on Retention, Reconditioning, and Extinction of the Conditioned Skin Conductance Response


  • The authors wish to express their thanks to the following colleagues who assisted with the carrying out of this study: Sarah Lusk, for assistance with data collection; Sheree Ting and Wendy Spotts, for assistance with record reading; and Diane Filion, for preparation of figures. We also acknowledge the considerable contribution by Jeffrey Braaten, and report with sorrow the death of this friend and colleague on September 18, 1987. This research was supported by NIMH grant MH40496.

Address requests for reprints to: Anne M. Schell, Department of Psychology, Occidental College, Los Angeles, CA 90041.


Discriminative classical conditioning of skin conductance responses (SCRs) was studied in 163 college students as a function of four variables: CS type (potentially phobic versus neutral conditioned stimuli), Sex of the subject, Interstimulus interval (ISI) during conditioning (.5 versus 8 s), and Retention interval between conditioning and retention assessment (1 versus 6 months). CS type did not affect acquisition, retention, or reconditioning of the differential conditioned responses. The effect of CS type was highly significant during extinction, with differential SCRs to CS+ and CS− being greater with potentially phobic conditioned stimuli. This was true for both sexes, both the .5-s and the 8-s ISI, and after a 1-month or a 6-month retention interval. Moreover, SCRs conditioned to phobic conditioned stimuli with the .5-s ISI persisted even after subjects' cognitive expectancy of the UCS, which was measured on a trial-by-trial basis, had completely extinguished. The results indicate that the effect of potentially phobic conditioned stimuli on the conditioned skin conductance response is unique to resistance to extinction—they affect not learning but unlearning of the autonomic response.