Physiological, Cognitive and Motor Assessments of Systematic Desensitization

Twenty-four snake phobic subjects were randomly assigned to one of four conditions in order to test directly the mechanism underlying Systematic Desensitization therapy. Only those Ss who were treated with systematic desensitization showed significant reductions in physiological cognitive and motor estimates of fear. No Treatment Control and Hierarchy-Yoked Ss did not improve on a single measure after treatment. Relaxation-Yoked Ss did report significant decrements in fear after treatment, but their verbal fear decrement was not sustained when proximity to the phobic stimulus was increased. The results supported Wolpe's contention that systematic desensitization operates on the basis of the reciprocal inhibition principle. Reductions in both skeletal-motor and sympathetic measures of fear were found to be closely associated with concomitant reductions in verbal and motor estimates of fear.