Dopaminergic D Receptor Stimulation Affects Effort and Risk Preferences.

Background: Activation of D receptors has been related to successful goal-directed behavior, but it remains unclear whether D receptor activation causally tips the balance of weighing costs and benefits in humans. Here, we tested the impact of pharmacologically stimulated D receptors on sensitivity to risk, delay, and effort costs in economic choice and investigated whether D receptor stimulation would bias preferences toward options with increased costs in a cost-specific manner.

Methods: In a randomized, double-blind, placebo-controlled, parallel-group phase 1 study, 120 healthy young volunteers received either placebo or 1 of 3 doses (6 mg, 15 mg, or 30 mg) of a novel, selective D agonist (PF-06412562). After drug administration, participants performed decision tasks measuring their preferences for risky, delayed, and effortful outcomes.

Results: Higher doses of the D agonist increased the willingness to exert physical effort for reward as well as reduced the preference for risky outcomes. We observed no effects on preferences for delayed rewards.

Conclusions: The current results provide evidence that D receptor stimulation causally affects core aspects of cost-benefit decision making in humans.