Effect of lysergic acid diethylamide (LSD) on reinforcement learning in humans
bioRxiv (Cold Spring Harbor Laboratory) December 9, 2020 Jonathan W. Kanen, Qiang Luo, Mojtaba Rostami Kandroodi et al. 14 citations preprint
Lysergic acid diethylamide (LSD) increases the speed at which the brain updates the value of actions following feedback, particularly after rewards, and makes behavior more exploratory. In a within-subjects experiment, healthy volunteers received intravenous LSD or placebo and performed a probabilistic reversal learning task where they learned which of three stimuli was most often rewarded, with contingencies later reversing. Computational modeling showed LSD enhanced the reward learning rate and also elevated the punishment learning rate, while reducing stimulus stickiness—a measure of choice repetition regardless of outcomes. Conventional measures of immediate feedback sensitivity were unaffected. These findings suggest LSD induces a state of heightened plasticity that may help revise maladaptive associations in clinical settings.