Alexithymia may modulate decision making in patients with de novo Parkinson's disease

The aim of this study was to investigate whether and how alexithymia may influence decision making under conditions of uncertainty, assessed using the Iowa Gambling Task, in patients with newly diagnosed, untreated (de novo) Parkinson's disease, as previously reported for healthy subjects. Twenty-four patients with de novo Parkinson's disease underwent a neuropsychological and neuropsychiatric assessment, including the Toronto Alexithymia Scale, the Geriatric Depression Scale Short Form, and the Iowa Gambling Task (IGT). The assessment showed that 12 patients were alexithymic and 12 were non-alexithymic; seven patients were found to be mildly depressed and 17 non-depressed. Alexithymic and non-alexithymic patients did not differ in the IGT total score; however, significant differences emerged across the third block of the IGT, in which the alexithymic patients outperformed the nonalexithymic patients. Depression did not influence IGT performance. Alexithymia may modulate decision making, as assessed with the IGT; alexithymia could be associated with faster learning to avoid risky choices and negative feedback, as previously reported in some studies conducted in anxious or depressed patients.