Dopaminergic therapy disrupts decision-making in impulsive-compulsive Parkinsonian patients.

Impulsive-compulsive behaviors (ICB) are common non-motor symptoms of Parkinson's disease (PD) often associated with dopaminergic drugs (DD) therapy. We investigated the acute effects of DD on decision-making in PD patients with ICB (ICB+) and without it (ICB-), and in healthy controls (HC). Participants performed a risk-based decision-making task twice, with PD patients tested before (DD OFF) and after (DD ON) DD intake. In DD OFF, all groups developed a risk-averting strategy. In DD ON, ICB+ patients (but not ICB- nor HC) reverted to riskier choices. We conclude that DD has a specific strong acute effect on ICB+ patients' decision-making.