Tourette's syndrome (TS): cognitive performance in adults with uncomplicated TS

Tourette's syndrome (TS) is a neurodevelopmental disorder associated with frontostriatal dysfunction. The extent of any cognitive impairment associated with uncomplicated TS is unclear, as comorbid psychiatric symptomatology is thought to contribute to cognitive deficits. Previous studies have found evidence of mild performance deficits, most commonly on tasks that involve inhibitory processes. The present study evaluated this in carefully screened adult participants with TS. The findings showed the TS group to perform more poorly on one test involving behavioral inhibition (sentence completion), but did not provide strong support for an interpretation based solely on inhibitory deficits, and there was no evidence of impairment on another behavioral inhibition task (flanker test). There were also no differences between the groups on tasks involving working memory (n-back), task switching, or object alternation learning. The findings provide further evidence that uncomplicated TS is associated with only mild, circumscribed impairment. The nature of any impairment is discussed.