Reward-Based Reinforcement Learning in Altered Among Individuals with a History of Major Depressive Disorder and Psychomotor Retardation Symptoms
Year: 2021
Type: preprint
Study design: Observational Study
Abstract: Background: Reward-based reinforcement learning impairments are common in major depressive disorder, but it is unclear which reward-based reinforcement learning is disrupted in remitted major depression (rMDD). As the neurobiological substrates that implement reward-based RL are also strongly implicated in psychomotor retardation (PmR), the present study sought to test whether reward-based reinforcement learning is particularly altered in rMDD individuals with past PmR. Methods: Three groups of individuals (1) rMDD with past PmR (PmR+, N=34), rMDD without past PmR (PmR-, N=44) and healthy controls (N=90) completed a reward-based reinforcement learning task. Computational modeling was applied to test for group differences in model-derived parameters – specifically, learning rate, reward sensitivity, and value estimates. Results: Compared to controls, rMDD PmR + exhibited lower learning rates, but not reduced reward sensitivity. Relative to rMDD PmR-, rMDD PmR + exhibited reduced value estimation early, but not later, in the reinforcement learning task. Follow-up analyses indicated that the results were not due to current psychopathology symptoms.Conclusions: Results indicate that a history of PmR predicts altered reward-based reinforcement learning in rMDD. Abnormal reward-related reinforcement learning may reflect a scar of past depressive episodes that contained psychomotor symptoms, or a trait-like deficit that preceded these episodes.
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: gold
OpenAlex ID: W4200618152