The spectral analysis of hypnotic performance with respect to "absorption"

In factor analyses of the hypnosis scales, the essential result is that the items form a continuous, 2-dimensional fan-shaped pattern. This continuum is referred to as the "spectrum of hypnotic performance." "Special analysis" is introduced as an exploratory procedure which makes use of this notion of continuum or spectrum. Spectral analysis consists of a graphical display of the level of latent correlation between a variable and individual hypnotic performances when the latter are arranged according to their position in the spectrum. The spectral analysis of hypnotic performance with respect to absorption is illustrated using data from a sample of 160 Ss. The results indicate that absorption is more strongly related to difficult hypnotic performances than to easy ones. In particular, illustrative item characteristic curves are presented to show that although easy hypnotic performances do not require the processes tapped by individual differences in absorption, a certain level of absorption is necessary to pass difficult hypnotic items. In addition, a high level of absorption may be sufficient in and of itself for difficult hypnotic performances. These results are discussed in light of some speculations by Shor, M. T. Orne, and O'Connell (1962) and Tellegen (1978/1979) concerning the differential contribution of ability components to performance on difficult hypnotic suggestions. The results are also related to a variety of work in social psychological models of hypnotic performance.