Decision-making impairments in Parkinson's disease as a by-product of defective cost–benefit analysis and feedback processing

Abstract

SUMMARY  Studies examining decision-making in people with Parkinson's disease (PD) show impaired performance on a variety of tasks. However, there are also demonstrations that patients with PD can make optimal decisions just like healthy age-matched controls. We propose that the reason for these mixed findings is that PD does not produce a generalized impairment of decision-making, but rather affects sub-components of this process. In this review we evaluate this hypothesis by considering the empirical evidence examining decision-making in PD. We suggest that of the various stages of the decision-making process, the most affected in PD are (1) the cost–benefit analysis stage and (2) the outcome evaluation stage. We consider the implications of this proposal for research in this area.