Journal of Personality and Social Psychology Copyright 1998 by the American Psychological Association, Inc. 1998, Vol. 75, No. 6, 1604 1613 0022-3514/98/$3.00 Self-Fulfilling Prophecy and Hypnotic Response Are Not the Same Thing Grant Benham, Shannon Bowers, Michael Nash, and Robert Muenchen University of Tennessee, Knoxville The authors used the "bogus-item" methodology originally used by C. Wickless and I. Kirsch (1989) to examine the effects of response expectancy manipulations on subjects' subsequently measured hypnotizability scores. The results of the first experiment failed to replicate Wickless and Kirsch's (1989) findings that surreptitious confirmation of suggested items (the bogus-item manipulation) leads to higher scores on subsequently measured hypnotic responsiveness. The second experiment tested if, in fact, response expectancies were enhanced by the bogus-item manipulation, and the manipulation's effect on behavioral and subjective responsiveness to hypnosis was reexam- ined. A significant increase was found in response expectancies as a result of the bogus item expectancy manipulation, but again no evidence that this manipulation led to increased hypnotic responsiveness was found. Hypnotic responsiveness may not be as reactive to expectancy manipula- tions as previously claimed, and it is suggested that the notion of hypnotic responsiveness as a traitlike ability is viable. Broadly sketched, social learning and contextualist theories minimize the importance of traitlike predispositions and cham- pion the influence of response expectations and reciprocal role interactions. Even when stability in performance obtains and change across contexts is quite minimal, it is difficult to empiri- cally test to what extent this stability is due to powerfully endur- ing social influences or traitlike characteristics. The experi- menter is faced with two challenges: (a) identifying a behavior that is both stable across contexts and at the same time novel enough to be relatively unburdened by preexisting expectational sets--if this condition is met, it becomes possible to test if proximal manipulation of response expectations affects the level of performance and establishes stability across time; and (b) identifying a behavior that is both stable across contexts and has two distinct theories accounting for this stability, one trait- based and the other based on social learning. If this condition is met, empirical work can plausibly begin to unravel the relative merit of each theory regarding the source of the stability. Individ- ual differences in hypnotic responsiveness are well suited on both counts. Most researchers, regardless of theoretical perspective, agree that the degree to which a person responds to hypnosis is re- markably stable over time. Perhaps the most compelling illustra- tion of this stability is the long-term follow-up study in which the Stanford Hypnotic Susceptibility Scale (SHSS), Form A, was readministered to participants 10 to 25 years after it was first administered to them (Piccione, Hilgard, & Zimbardo, 1989). Overall, the test-retest reliability for hypnotic susceptibility was .71. This kind of stability compares favorably with test-retest reliabilities for IQ tests over similar periods of time. 1 Grant Benham, Shannon Bowers, and Michael Nash, Department of Psychology, University of Tennessee, Knoxville; Robert Muenchen, Sta- tistical Consulting Center, University of Tennessee, Knoxville. Correspondence concerning this article should be addressed to Mi- chael Nash, Department of Psychology, University of Tennessee, Knox- ville, Tennessee 37996. Electronic mail may be sent to mnash@utk.edu. There remains, however, considerable disagreement about why this stability obtains: Does this stability reflect an enduring cognitive ability or personality trait of "hypnotic susceptibility," or is it a product of response expectations that consolidate at first testing? According to the trait view, people vary (roughly normally) in their capacity for experiencing hypnosis; individual differences in response to hypnosis are then simply a reflection of people's differing on a cognitive processing ability we call hypnotic susceptibility (e.g., Hilgard, 1965; Piccione et al., 1989). The nature of this cognitive ability is elusive, but it may have its foundation in genetics (heritability index h 2 of .64; Morgan, 1973, p. 58), cognitive processing (Tellegen & Atkin- son, 1974), and brain physiology (Graffin, Ray, & Lundy, 1995). In contrast, response expectancy theory (Kirsch, 1985) proposes that individual differences in hypnotizability are pri- marily the result of differences in the participant's response expectations, and that the temporal stability of hypnotic perfor- mance reflects enduring expectancies rather than a fixed person- ality trait. Proponents of the response expectancy theory contend that a person's belief about his or her hypnotic ability is the primary determinant of how many suggestions he or she re- sponds to successfully. According to this theory, if naive partici- pants are exposed to procedures that increase their expectations of how well they will do in hypnosis, they will in fact score higher than controls will on a measure of hypnotic susceptibility when subsequently tested. Whether individual differences in hypnotizability reflect the operation of a stable trait or are in- stead a function of response expectancies also has important clinical implications. As Kirsch states, "It is possible that, with sufficiently strong response expectancies, all individuals would show high levels of hypnotic response" (1985, p. 1196). The question of whether manipulation of proximal response expectancies might affect hypnotic responsiveness was origi- nally studied by Wickless (1987) and was later reported by 1A 13-year test-retest reliability for the Wechsler Adult Intelligence Scale IQ test is reported as .73 (Kangas & Bradway, 1971). 1604