Modulation of attentional bias by hypnotic suggestion: experimental evidence from an emotional Stroop task

ABSTRACT

Hypnosis is considered a unique tool capable of modulating cognitive processes. The extent to which hypnotic suggestions intervenes is still under debate. This study was designed to provide a new insight into this issue, by focusing on an unintentional emotional process: attentional bias. In Experiment 1, highly suggestible participants performed three sessions of an emotional Stroop task where hypnotic suggestions aiming to increase and decrease emotional reactivity towards emotional stimuli were administered within an intra-individual design. Compared to a baseline condition (without hypnotic suggestion), a significant increase in attentional bias was found when a hypnotic suggestion to increase emotional reactivity was administered. In contrast, the bias was eliminated when a suggestion to decrease emotional reactivity was administered. Experiment 2 investigated the effect of session repetition on attentional bias across three successive experimental sessions without hypnosis, and showed that the emotional Stroop effect did not vary across sessions. Hence, session repetition could not account for part of the modulation of attentional bias in Experiment 1. Taken together, the results suggest that specific hypnotic suggestions can influence elicitation of unintentional emotional processing. The implications are discussed regarding the locus of intervention of hypnotic suggestion in cognitive and emotional processes.

KEYWORDS:

• Hypnotic suggestion
• hypnosis
• attentional bias
• Stroop task
• emotional Stroop task

Acknowledgements

We are thankful to Maria Augustinova and Ludovic Ferrand who permit us to use their French translation of the Harvard group scale of Susceptibility form A (Augustinova & Ferrand, 2012). We would like to thank Rolland Zielke as well, psychologist and hypnotherapist who recorded the full script of this translated scale.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 The fact that the ideomotor suggestion was passed does not rule out the possibility that some participants raised or lowered their arm intentionally, which in this case is not an indicator of hypnotic response. Moreover, although the ideomotor suggestion and the emotional intensity suggestion were associated, there is a possibility that both suggestions were processed independently and that a participant could have passed the ideomotor suggestion without passing the emotional intensity suggestion, or the reverse. To counteract this limit in our participant selection, a statistical analysis was performed with all participants without taking into account the response to the ideomotor cue. The results are accessible in the supplemental materials and were identical in the final analysis.