Ž . International Journal of Psychophysiology 27 1997 18 Somatosensoryevent-related potential changes to painful stimuli during hypnotic analgesia: anterior cingulate cortex and anterior temporal cortexintracranial recordings Juri D. Kropotov  ,a , Helen J. Crawford b , Yuri I. Polyakov c a L aboratory of Neurobiology of Action Programming, Institute of the Human Brain of Russian Academy of Sciences, Ul. Acad. Pa®lo®a 12, 19376 St. Petersburg, Russia b Neurocognition L aboratory, Department of Psychology, Virginia Polytechnic Institute and State Uni ®ersity, Blacksburg, Virginia 24061, USA c Institute of the Human Brain of Russian Academy of Sciences, St. Petersburg, Russia Received 30 June 1995; revised 28 June 1996; accepted 12 August 1996 Abstract The present study examined neurophysiological correlates of pain and pain control by recording intracranial Ž . somatosensory event-related potentials SERPs to painful cutaneous stimuli in two female patients with Ž. Ž. obsessive  compulsive disorder bearing multiple intracranial electrodes during conditions of a attention and b hypnotically suggested analgesia. Intracranial electrodes were located in the anterior cingulate cortex, amygdala, temporal cortex, and parietal cortex. No changes were observed in the SERPs of the hypnotically unresponsive patient. In the hypnotically responsive patient, reduced pain perception during suggested hypnotic analgesia was Ž. accompanied by a a significant reduction of the positive SERP component within the range of 140 160 ms Ž . Ž. post-stimulus in the left anterior cingulate cortex Shaltenbrandt atlas: 29.12ry7.42r32.41 , and b a significant enhancement of the negative SERP component within the range of 200  260 ms in the left anterior temporal cortex Ž . Brodmann area 21 . No significant changes were observed in the amygdala or the scalp-recorded Fz. The present studyis the first to demonstrate the involvement of the anterior cingulate cortexand the anterior temporal cortexin the control of pain with hypnotically suggested analgesia.  1997 Elsevier Science B.V. Keywords: Attention; Anterior cingulate cortex; Temporal cortex; Intracerebral recording; Somatosensory event related potentials; Pain; Hypnosis; Hypnotic analgesia; Hypnotic susceptibility; Obsessive  compulsive disorder 1. Introduction The effectiveness of hypnosis in the relief of Ž pain has been well documented for reviews, see  Corresponding author. Hilgard, 1975; Orne and Dinges, 1984; Hilgard . and Hilgard, 1994 , yet the neurophysiological basis for hypnotically suggested analgesia needs further investigation. Highly hypnotizable persons are hypothesized to possess a stronger attentional filter to distracting stimuli associated with the Ž fronto  limbic attentional system e.g. Crawford et 0167-8760r97r$17.00  1997 Elsevier Science B.V. All rights reserved. Ž . PII S0167-8760 97 00785-X