The orbitofrontal cortex and the dopaminergic system are structures involved in managing impulsivity and sensibility to reinforcements, and both are typically impaired in Parkinson's disease (PD). Also, l-DOPA treatment can contribute to the development of the ‘Dopamine Dysregulation Syndrome’, a syndrome that can influence the patients' personality and lead to risk-taking behaviors. In this study, we describe the case of a 42-year-old woman (LT) affected by juvenile PD, treated with both l-DOPA and dopamine agonists, who showed a sudden onset of pathological gambling (PG), as the only neuropsychiatric symptom. We assessed LT with a full neuropsychological battery and the Iowa Gambling Task (IGT), in order to describe her specific failure in decision making. LT's performance on the IGT is compared with that of 15 non-demented PD patients under therapy with dopamine agonists and no behavioral dysregulations and with that of 16 age- and education-matched healthy subjects. Results showed fully preserved memory, executive functions, and reasoning abilities for LT, but a remarkable and stable impairment in the IGT. Performance of LT on the IGT is significantly lower than that of both control groups. This case shows, for the first time, that high cognitive functioning and preserved executive functions are no guarantee for advantageous decision making, and that the onset of PG is consistent with selective orbitofrontal disruption and side-effects of dopamine agonist therapy. It is also showed that the IGT is a useful neuropsychological device to detect specific risk-taking behaviors, which compromise functioning in real life.
Background: Parkinson's disease (PD) is frequently characterized by cognitive and affective dysfunctions. The “Parkinson Neuropsychometric Dementia Assessment” (PANDA) is a screening tool designed for the early detection of mild cognitive impairment as well as dementia in PD. The PANDA is already validated in German and in French. Objective: The aim of the present work was to provide normative data for the Italian-speaking population, Swiss regions included; moreover, the effectiveness of the PANDA compared to the Mini Mental State Examination (MMSE) was tested. Methods: One-hundred and eleven PD patients with and without cognitive impairment and one-hundred and three matched healthy subjects participated at this study; all patients underwent an extensive neuropsychological evaluation. Results: A PANDA total score of 13 appeared to be the most fitting cut-off with a sensitivity of 96.6% and a specificity of 82.2%; with the MMSE, the same value of sensitivity but with a specificity of 72,4% was reached only by adopting a cut-off of 28. Moreover, a PANDA range of 13–17 appeared to be suggestive for possible cognitive disturbance. Conclusions: The present work provides evidence for the effectiveness of the PANDA in evaluating cognitive deficits also in PD Italian-speaking patients, even when their pathological degree is still initial or very mild.