Premonitory urges in Tourette's syndrome

Tourette's syndrome traditionally has been viewed as a hyperkinetic movement disorder characterized by involuntary motor and phonic tics. Many patients, however, describe their tics as a voluntary response to premonitory urges. This cross-sectional study evaluated premonitory urges and related phenomena in subjects with tic disorders.

A total of 135 subjects with tic disorders, aged 8 to 71 years, completed a questionnaire concerning their current and past tic symptoms. Subjects were asked to describe and, if possible, localize their premonitory urges. The Yale Global Tic Severity Scale was used to assess current tic severity. The method of case finding does not provide prevalence data for premonitory urges.

Ninety-three percent of the subjects reported premonitory urges. Anatomical regions with the greatest density of urges were the palms, shoulders, midline abdomen, and throat. Eighty-four percent of the subjects reported that tics were associated with a feeling of relief. A substantial majority (92%) also indicated that their tics were either fully or partially a voluntary response to the premonitory urges.

While epidemiological studies of tic disorders have yet to incorporate questions concerning premonitory urges, these results suggest that such urges may be commonplace in adolescent and adult subjects with tic disorders. These results challenge the conventional wisdom that tic behaviors are wholly involuntary in character. They also implicate brain regions involved in the processing of sensorimotor information in the pathobiology of tic disorders.