The contribution of relaxation and expectancy to fear reduction via graded, imaginal exposure to feared stimuli

Speech phobic subjects received five treatment sessions under either positive or neutral expectancy set. Therapy conditions included hierarchy exposure with contiguous relaxation (desensitization), exposure with noncontiguous relaxation, exposure only, and no-treatment. Expectancy had virtually no outcome effects. Desensitization was superior to the other conditions on subjective outcome measures. In contrast to the two exposure conditions without contiguous relaxation, desensitization resulted in increased imagery vividness, greater cardiovascular response to the first visualization of the initial hierarchy scene, and greater declines in cardiovascular response within repetitious visualizations of scenes and across initial visualizations of increasingly anxiety-provoking scenes. Expectancy significantly influenced both fear ratings and cardiovascular response to scenes during the first session, the latter effect disappearing after the first session. The results are discussed in terms of recent theorizing regarding the role of relaxation and expectancy in desensitization.