Hypnosis in increasingly used in clinical contexts to improve pain management and is supported by experimental research showing reduced pain perception to controlled nociceptive stimuli. This study investigated the spatial selectivity of focused hypnotic analgesia (FHA), a technique used to reduce pain in one body part. The suggestion was administered on the arm of 40 participants, and contact heat stimuli were randomly applied on both arms before, during and after FHA. Pain intensity and unpleasantness were assessed after each stimulus using numerical ratings scales. Results showed a significant decrease in pain intensity and unpleasantness for the protected arm during FHA as compared to before and after, whereas no modulation was evidenced for the unprotected arm. Ratings were significantly different between the two arms only during FHA. These results were observed regardless of the level of hypnotizability. This confirms that FHA can selectively modulate pain perception, both its sensory-discriminative and emotional-cognitive components, and restrict its effects on a targeted area without affecting perception of stimuli applied on other body parts.
Caekenberghe et al. (Sun,) studied this question.