Dopamine regulates decision thresholds in human reinforcement learning in males

TY - JOUR

T1 - Dopamine regulates decision thresholds in human reinforcement learning in males

AU - Chakroun, Karima

AU - Wiehler, Antonius

AU - Wagner, Ben

AU - Mathar, David

AU - Ganzer, Florian

AU - van Eimeren, Thilo

AU - Sommer, Tobias

AU - Peters, Jan

N1 - © 2023. Springer Nature Limited.

PY - 2023/9/4

Y1 - 2023/9/4

N2 - Dopamine fundamentally contributes to reinforcement learning, but recent accounts also suggest a contribution to specific action selection mechanisms and the regulation of response vigour. Here, we examine dopaminergic mechanisms underlying human reinforcement learning and action selection via a combined pharmacological neuroimaging approach in male human volunteers (n = 31, within-subjects; Placebo, 150 mg of the dopamine precursor L-dopa, 2 mg of the D2 receptor antagonist Haloperidol). We found little credible evidence for previously reported beneficial effects of L-dopa vs. Haloperidol on learning from gains and altered neural prediction error signals, which may be partly due to differences experimental design and/or drug dosages. Reinforcement learning drift diffusion models account for learning-related changes in accuracy and response times, and reveal consistent decision threshold reductions under both drugs, in line with the idea that lower dosages of D2 receptor antagonists increase striatal DA release via an autoreceptor-mediated feedback mechanism. These results are in line with the idea that dopamine regulates decision thresholds during reinforcement learning, and may help to bridge action selection and response vigor accounts of dopamine.

AB - Dopamine fundamentally contributes to reinforcement learning, but recent accounts also suggest a contribution to specific action selection mechanisms and the regulation of response vigour. Here, we examine dopaminergic mechanisms underlying human reinforcement learning and action selection via a combined pharmacological neuroimaging approach in male human volunteers (n = 31, within-subjects; Placebo, 150 mg of the dopamine precursor L-dopa, 2 mg of the D2 receptor antagonist Haloperidol). We found little credible evidence for previously reported beneficial effects of L-dopa vs. Haloperidol on learning from gains and altered neural prediction error signals, which may be partly due to differences experimental design and/or drug dosages. Reinforcement learning drift diffusion models account for learning-related changes in accuracy and response times, and reveal consistent decision threshold reductions under both drugs, in line with the idea that lower dosages of D2 receptor antagonists increase striatal DA release via an autoreceptor-mediated feedback mechanism. These results are in line with the idea that dopamine regulates decision thresholds during reinforcement learning, and may help to bridge action selection and response vigor accounts of dopamine.

KW - Humans

KW - Male

KW - Dopamine

KW - Levodopa/pharmacology

KW - Haloperidol/pharmacology

KW - Men

KW - Plastic Surgery Procedures

U2 - 10.1038/s41467-023-41130-y

DO - 10.1038/s41467-023-41130-y

M3 - SCORING: Journal article

C2 - 37666865

VL - 14

SP - 5369

JO - NAT COMMUN

JF - NAT COMMUN

SN - 2041-1723

IS - 1

ER -