Social and economic reasoning in Tourette syndrome

Aims In Tourette Syndrome (TS), striatal dysfunction could affect the functioning of the frontal cortex, leading to changes in cognition and social behaviour. This study investigated social and economic reasoning in patients with TS. Methods 16 patients with TS and 20 neurologically intact controls completed three reasoning tasks that involved making judgements about mental states (Theory of Mind) and an economic decision making task. The tasks used were the “Eyes Test”, a “socially competitive emotions” task, a humourous cartoons task featuring sarcasm and irony, and a version of the Ultimatum Game. Executive functions were assessed using the FAS verbal fluency test and a black and white Stroop task. Results Patients with TS exhibited significant impairments on all four of the tasks selected to assess social and economic reasoning. These difficulties were evident despite the finding that patients did not exhibit significant executive deficits on the verbal fluency or inhibitory measures. Conclusions TS is associated with deficits on a range of tasks involving social and economic reasoning. Impairments on similar tasks have been reported in patients who have dysfunction of ventromedial prefrontal cortex. The observed deficits could imply that patients with TS exhibit dysfunction within frontostriatal pathways involving this region.