Social modeling influences on sensory decision theory and psychophysiological indexes of pain.

Ss exposed to social models dissimulating tolerance or intolerance generally exhibit matching behavior in their verbal ratings of painful stimulation. It has been unclear, however, whether these changes reflect voluntary alteration of evidence or genuine changes in distress. The present study examined nonpalmar skin potential in addition to palmar skin conductance and heart rate (HR) indexes of psychophysiological response to electric shock and evaluated verbal expressions of pain with sensory decision theory methodology. Of 20 female undergraduate volunteers, 10 served as controls, and 10 were exposed to a tolerant female model. Both the S and the model verbalized ratings of discomfort provoked by a series of electric shocks of increasing intensity. Ss then underwent a series of preselected random shocks. Sensory decision theory analyses revealed lower discriminability of the shocks among Ss exposed to a tolerant model. Several indexes of nonpalmar skin potential and HR reactivity exhibited lower reactivity in the tolerant group. Tolerant modeling was also associated with decreases in subjective stess. The results are consistent with the position that changes in pain indexes associated with exposure to a tolerant model represent variations in fundamental characteristics of painful experiences as opposed to suppression of information. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)