The Effect of Different Types of Influence on an “Indirect-Direct” Form of a Scale of Sensory Suggestibility

Abstract

To overcome the use of a fragile ruse in indirect methods of assessing suggestiblity, an indirect-direct method was developed wherein subjects are cautioned that an announced sensory stimulus may not actually be presented. The scale consists of twelve tactual, auditory, and visual items. Each item is administered to the left and right sides of the body, and the method of presentation (e.g., progressive increase in intensity of stimulation) is varied. The scale is indirect in that stimuli are never presented to participants, contrary to their expectations; it is direct because they are cautioned that a stimulus might not actually be presented. The scale was shown to have acceptable internal consistency and test-retest reliability and resistance to influence by situational variables. There also was a leftside advantage which might be confounded with order of presentation. Five methods of presentation were not equally successful. Progressive Intensification of stimulation was the most successful, whereas Progressive Decrease in Intensification was least successful. The total scale score was significantly lower than when it was administered as an indirect scale. The lower suggestibility was attributed to an active-analytic attitude fostered by the admonitions and penalties included in the instructions for the indirect-direct method of administration. Comparisons between direct, indirect, and indirect-direct methods and a formal induction of hypnosis is useful in identifying different — sources of responsivity, including personality variables. Several implications for clinical practice were noted.