Effects of hypnotizability on performance of a stroop task and event-related potentials

The effect of hypnotizability on verbal reaction times and event-related po tentials during performance of a Stroop color-naming task was studied. The Stroop stimuli (colored words) were randomly presented to 5 high and 5 low hypnotizable subjects in the right and left peripheral visual fields juring both waking state and hypnotic induction conditions. Unlike studies in whi ch the Stroop stimuli were foveally presented to the: subjects, the highly hypnotizable subjects did not show prolonged verbal reaction times in eithe r waking or hypnotic conditions. There was a marked deterioration in perfor mance accuracy, however, for highly hypnotizable sub jeers during hypnosis. Event-related potentials indicated that the highly hypnotizable subjects s howed a reduced P3a amplitude and a decreased N2b latency to the visual sti muli in both waking and hypnotic conditions, suggesting a lack of orienting to or disengagement from peripherally occurring stimuli.