Hypnotic ability and baseline attention: fMRI findings from Stroop interference.

Abstract

A benchmark experimental conflict task, the Stroop interference effect, probes selective attention. Regarding individual differences, accounts from multiple independent research groups have shown that a specific suggestion to obviate word meaning can reduce the Stroop interference effect in high- but usually not low-hypnotizable participants. Here we report findings from functional magnetic resonance imaging (fMRI) showing that high-hypnotizable participants, compared with low-hypnotizables, may maintain a distinct baseline of attention even outside of hypnosis or suggestion. Although previous neuroimaging investigation of suggestion-induced Stroop reduction implicated a locus of brain regions prominently including the anterior cingulate cortex, here we observed suggestion-free group differences focal to the fusiform gyrus and pulvinar nucleus of the thalamus—regions associated with word reading and visual attention, respectively. We contextualize our findings in terms of earlier efforts that have attempted to link hypnotizability and baseline performance of attention.