Effects of social anxiety and facial expression on habituation of the electrodermal orienting response

Abstract

The present research examined electrodermal orienting to happy and angry faces as a function of social anxiety and threat of shock. A preliminary study using 569 undergraduate participants developed an adequate set of normative data of social anxiety for the Willoughby questionnaire (WQ) for use in subject selection. Electrodermal activity was measured in both high and low socially anxious subjects (N = 85) during exposure to 10 presentations of an angry face intermixed with 10 presentations of a happy face. Threat of shock (no-shock, shock work-up only, and shock work-up plus threat) was also manipulated. Skin conductance responses (SCRs) which occurred within 1-4 s of stimulus onset and trials-to-habituation constituted the data of primary interest. Although trials-to-habituation did not differ between angry and happy facial expressions, SCRs were larger to the angry face than to the happy face in both high and low socially anxious subjects. No differences in SCR magnitude were found as a function of threat of shock. The implications of these results for Ohman's functional-evolutionary model of social phobia are discussed, and alternative explanations in terms of prepotency and prior learning are examined.