Cognitive impulsivity in Parkinson's disease patients: assessment and pathophysiology.

Impulsivity may be induced by therapeutic interventions (dopamine replacement therapies and sub-thalamic nucleus (STN) stimulation) in patients with Parkinson's disease (PD). The present review has two goals. First, to describe the most frequently encountered facets of cognitive impulsivity and to stress the links between cognitive impulsivity and aspects such as reward-related decision making, risk-taking, and time-processing in healthy population. The most widely used related cognitive impulsivity paradigms are presented. Second, to review the results of studies on cognitive impulsivity in healthy volunteers and in patients with PD, the latter support the applicability and clinical relevance of this construct in PD population. Data show that PD treatments may favor impulsivity via different mechanisms. Suggestions on the roles of dopamine and STN in the pathophysiology of cognitive impulsivity are proposed.