Subjective ratings of pain correlate with subcortical-limbic blood flow: An fMRI study

Studies investigating the cerebral representations of pain using functional imaging techniques failed to elucidate the affective aspects of pain, This investigation used functional magnetic resonance imaging to measure pain-r elated changes in cerebral activity during painful stimulation with a stron g affective component. Vascular pain was induced via balloon dilatation of a dorsal foot vein of healthy volunteers. The subjects rated their perceive d pain uninterruptedly during imaging, allowing cerebral activity to be cor related with both stimulus function (boxcar) and, more importantly, subject ive ratings reflecting individual pain experience. The findings indicated s ignal increases in subcortical-limbic regions, particularly in the amygdala . This region is suggested to be involved in the affective dimension of pai n. Copyright (C) 2001 S. Karger AG. Basel.