Dopaminergic Modulation of Human Intertemporal Choice: A Diffusion Model Analysis Using the D2-Receptor Antagonist...

Area of Science:

• Neuroscience
• Cognitive Science
• Pharmacology

Background:

• Dopamine is crucial for reward processing, learning, and cognitive control.
• Temporal discounting, the tendency to devalue future rewards, is potentially modulated by dopamine.

Purpose of the Study:

• To investigate the effect of a D2 receptor antagonist (haloperidol) on temporal discounting and choice dynamics.
• To explore how dopamine influences reward magnitude effects on temporal discounting using computational models.

Main Methods:

• Administered a single dose of haloperidol (2 mg) or placebo to healthy participants.
• Utilized combined temporal discounting drift diffusion models to analyze choice dynamics.
• Employed hierarchical Bayesian parameter estimation for model analysis.

Main Results:

• Haloperidol significantly reduced temporal discounting (impulsive choice) and nondecision time compared to placebo.
• The effect of reward magnitude on discounting was not substantially altered by haloperidol.
• Model-free analyses corroborated the findings from computational modeling.

Conclusions:

• Haloperidol's effects suggest a role for dopamine in both higher-level temporal discounting and lower-level decision processes.
• Findings support the hypothesis of increased striatal dopamine neurotransmission under haloperidol.
• Model-based analyses provide insights into dopamine's contribution to value-based decision-making.