Extracorporeal 'phantom' tics in Tourette's syndrome.

Some tics are intentional movements made in an attempt to diminish uncomfortable sensations. These sensations, sometimes termed sensory tics, are focal and usually arise in the part of the body involved in the subsequent motor act. We report a patient whose sensations associated with tics were felt in other people and in objects. The discomfort associated with his out-of-body sensations was temporarily relieved by touching or scratching the object involved. The definition of premonitory sensations should be expanded to include extracorporeal sensations, and a history of external sensations should be sought in patients with Tourette's syndrome. Theories on the generation of tics must incorporate an explanation for extracorporeal sensations.