Cognitive functioning in Tourette syndrome.

Tourette Syndrome (TS) is characterized by tics, which are thought to reflect striatal dysfunction. Changes in functioning of the striatum in TS could lead to dysfunction in frontostriatal pathways involving cortical regions such as the dorsolateral prefrontal and anterior cingulate cortex. This in turn could result in deficits in specific cognitive processes and impairment on particular cognitive tasks. The aim of this review is to summarize the major findings of key studies of cognitive functioning in TS. The limitations and neurological implications of the reported findings are also discussed. Although the methodological limitations associated with many studies compel further investigation, tentative conclusions may be drawn from the available literature. While co-morbidities such as attention deficit-hyperactivity disorder (ADHD) may be associated with more significant executive dysfunction, we can conclude that patients without co-morbidities exhibit milder deficits in attention and inhibition-related processes. These cognitive difficulties are likely to reflect dysfunction with frontostriatal pathways involving the anterior cingulate circuit.