Hypnotic Ability and Baseline Attention: fMRI Findings From Stroop Interference Michael Lifshitz McGill University Amir Raz McGill University and Sir Mortimer B. Davis Jewish General Hospital, Montreal, Québec, Canada A benchmark experimental conflict task, the Stroop interference effect, probes selective attention. Regarding individual differences, accounts from multiple independent re- search groups have shown that a specific suggestion to obviate word meaning can reduce the Stroop interference effect in high- but usually not low-hypnotizable partic- ipants. 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. Keywords: attention, hypnosis, Stroop effect, fMRI, brain imaging In the classic Stroop task, proficient readers name the ink color of a displayed word (Stroop, 1935). Responding to the ink color of an incom- patible color word (e.g., the word “RED” inked in blue), participants are usually slower and less accurate than identifying the ink color of a congruent item (e.g., “LOT” or “RED” inked in red). This difference in performance constitutes the Stroop interference effect (SIE) and is one of the most robust and well-studied phenomena in attention research (MacLeod, 1991; MacLeod & MacDonald, 2000). With about four thousand citations to Stroop’s original paper, researchers widely believe that many aspects of skilled reading (e.g., the computation of letter identi- ties, word identity, phonology, and semantics) rely on automatic mental processes. Indeed, the standard account maintains that the processing of words occurs involuntarily (e.g., MacLeod, 1991; Neely, 1991) and that the SIE is therefore the “gold standard” for studying executive at- tention (MacLeod, 1992; cf. Augustinova & Ferrand, 2014). Here we apply functional mag- netic resonance imaging (fMRI) to a classic Stroop paradigm and illuminate the baseline neurocognitive differences between high- and low-hypnotizable individuals. Stroop and Hypnotic Phenomena Some early studies explored the potential marriage of Stroop and hypnosis (e.g., Blum & Graef, 1971; Blum & Wiess, 1986; Dixon, Bru- net, & Laurence, 1990; Dixon & Laurence, This article was published Online First April 20, 2015. Michael Lifshitz, Integrated Program in Neuroscience, McGill University; Amir Raz, Departments of Psychiatry, Neurology and Neurosurgery, and Psychology, McGill Uni- versity, Lady Davis Institute for Medical Research and Clinical Neuroscience and Applied Cognition Laboratory, Institute of Community and Family Psychiatry, Sir Mortimer B. Davis Jewish General Hospital, Montreal, Québec, Canada. Michael Lifshitz acknowledges a Francisco J. Varela Research Award from the Mind and Life Institute and a Vanier Canada Graduate Scholarship from the Natural Sci- ences and Engineering Research Council of Canada (NSERC). Dr. Amir Raz acknowledges funding from the Canada Research Chair program, Discovery and Discovery Acceleration Supplement grants from NSERC, Canadian Institutes of Health Research, and the Volkswagen Founda- tion (VolkswagenStiftung). Correspondence concerning this article should be ad- dressed to Amir Raz, Clinical Neuroscience and Applied Cognition Laboratory, Institute of Community and Family Psychiatry, Sir Mortimer B. Davis Jewish General Hospital, 4333 Chemin de la Côte-Sainte-Catherine, Montreal, QC H3T 1E4, Canada. E-mail: amir.raz@mcgill.ca This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Psychology of Consciousness: Theory, Research, and Practice © 2015 American Psychological Association 2015, Vol. 2, No. 2, 134 –143 2326-5523/15/$12.00 http://dx.doi.org/10.1037/cns0000050 134