This study will investigate how the sensitivity to touch and smell in patients with Tourette syndrome (TS) may differ from that of people without TS. TS is a neurological disorder that causes people to have uncontrolled movements called "tics." A tic can also be vocal, like a cough or bark or string of bad words. The tic is preceded by a "premonitory urge" that may feel like an itch or pressure that builds until the tic occurs. To some patients, the tic feels like a response to an involuntary sensation. In patients with TS, sensory information may be processed differently than it is in people without TS. This study will compare how strong a sensation feels in TS patients and healthy volunteers. It will also look for muscle activity that may be responsible for the feelings in the area of the tic.