PAIN-RELATED CEREBRAL POTENTIALS IN PATIENTS WITH FRONTAL OR PARIETALLOBE LESIONS

The present study investigated the processing of painful electrical st imuli in patients with unilateral frontal or parietal lobe damage and matched control subjects. Patients with frontal lesions showed increas ed pain thresholds when the stimuli were administered contralateral to the lesion. While the peak-to-peak amplitudes of the N150/P250 compon ents of the somatosensory potentials increased linearly with stimulus intensity in the control subjects, the responses in the frontal group did not change significantly between stimulation at pain and tolerance threshold. There was no evidence for altered pain processing in patie nts with parietal lobe lesions. The findings of the present study supp ort the hypothesis of an involvement of the frontal cortex in pain per ception in humans.