SOMATOSENSORY EVENT-RELATED POTENTIAL CHANGES TO PAINFUL STIMULI DURING HYPNOTIC ANALGESIA - ANTERIOR CINGULATE CORTEX AND ANTERIOR TEMPORAL CORTEX INTRACRANIAL RECORDINGS

The present study examined neurophysiological correlates of pain and p ain control by recording intracranial somatosensory event-related pote ntials (SERPs) to painful cutaneous stimuli in two female patients wit h obsessive-compulsive disorder bearing multiple intracranial electrod es during conditions of (a) attention and (b) hypnotically suggested a nalgesia. Intracranial electrodes were located in the anterior cingula te cortex, amygdala, temporal cortex, and parietal cortex. No changes were observed in the SERPs of the hypnotically unresponsive patient. I n the hypnotically responsive patient, reduced pain perception during suggested hypnotic analgesia was accompanied by (a) a significant redu ction of the positive SERF component within the range of 140-160 ms po st-stimulus in the left anterior cingulate cortex (Shaltenbrandt atlas : 29.12/-7.42/32.41), and (b) a significant enhancement of the negativ e SERF component within the range of 200-260 ms in the left anterior t emporal cortex (Brodmann area 21). No significant changes were observe d in the amygdala or the scalp-recorded Fz. The present study is the f irst to demonstrate the involvement of the anterior cingulate cortex a nd the anterior temporal cortex in the control of pain with hypnotical ly suggested analgesia. (C) 1997 Elsevier Science B.V.