Psychological accounts of hypnosis have hypothesized that hypnosis
and attention might share similar mechanisms and that hypnosis
simply represents an extensive state of reduced attention. This
assumption implies that reports of pain and electrocortical
brain responses to painful stimulation should be similarly reduced
when subjects are exposed to suggestions of hypnotic analgesia
(HA) or requested to distract their attention from painful stimuli
(distraction of attention: DA) as compared to a control condition
(CC). To test this hypothesis, we recorded event-related electrical
brain potentials to noxious laser-heat stimuli and pain reports
during HA, DA, and CC from subjects highly susceptible to hypnotic
suggestions. Pain reports were significantly reduced during
HA and DA as compared to CC. The amplitudes of the late
laser-evoked brain potential (LEP) components N200 and P320
were also significantly smaller during DA than during CC. However,
no significant difference of these late LEP amplitudes was obtained
for HA as compared to CC. Results indicate that hypnotic analgesia
and distraction of attention represent different mechanisms
of pain control and involve different brain mechanisms.