Focused hypnotic analgesia: local and remote effects.

Suggestion for hypnotic analgesia aimed at a specific body area is termed "focused hypnotic analgesia". It is not clear, however, whether this analgesia is limited to a specific body location or spread all over the body. Focused hypnotic analgesia was studied, in response to ascending electrical stimuli, when analgesia and stimulation were applied to the same area (local), and when analgesia was applied to one location and stimulation was delivered to a different area (remote). The face or leg served alternately as the local or remote areas, and the effect was tested in 12 high-hypnotizable (HH) and 13 low-hypnotizable (LH) subjects. Hypnotic analgesia in the local site produced a significant pain reduction compared to the remote site in HH subjects (P<0.0001) but not in LH subjects (P=0.68). As stimuli increased in intensity the reduction in pain as a result of hypnosis was larger both in HH and LH subjects (P<0.0001). Nevertheless, significant analgesia occurred in the 3 highest intensities in the local and remote location of HH subjects, but only in 2 highest intensities in the local and 1 in the remote of LH subjects. We conclude that in HH subjects focused hypnotic analgesia is mostly confined to the area aimed at, but some spread of analgesia to remote areas cannot be dismissed all together. Alternatively, this "spread" of analgesia could be due to a placebo effect in the remote area. Focused hypnotic analgesia requires increased attention to the body area aimed at, unlike analgesia achieved by distraction of attention.