Thermosensory activation of insular cortex

Temperature sensation is regarded as a submodality of touch, but evidence s uggests involvement of insular cortex rather than parietal somatosensory co rtices. Using positron emission tomography (PEI), we found contralateral ac tivity correlated with graded cooling stimuli only in the dorsal margin of the middle/posterior insula in humans. This corresponds to the thermorecept ive- and nociceptive-specific lamina I spinothalamocortical pathway in monk eys, and can be considered an enteroceptive area within limbic sensory cort ex. Because lesions at this site can produce the poststroke central pain sy ndrome, this finding supports the proposal that central pain results from l oss of the normal inhibition of pain by cold. Notably, perceived thermal in tensity was well correlated with activation in the right (ipsilateral) ante rior insular and orbitofrontal cortices.