Domain-Specific Working Memory, But Not Dopamine-Related Genetic Variability, Shapes Reward-Based Motor Learning

Area of Science:

• Neuroscience
• Motor Learning
• Cognitive Psychology

Background:

• Rewarding feedback enhances motor learning retention but causes significant interindividual variability.
• Understanding factors influencing this variability is crucial for optimizing rehabilitation strategies.
• Previous research highlights the need to identify predictors of success in reward-based motor learning.

Purpose of the Study:

• To investigate the association between working memory capacity (spatial, verbal, and rotation) and genetic profiles related to dopamine with performance in reward-based motor tasks.
• To identify key factors contributing to individual differences in reward-based motor learning.
• To explore the role of spatial working memory (SWM) and rotation working memory (RWM) in motor task success.

Main Methods:

• A large cohort (n=241) of both sexes performed two reward-based motor tasks with binary feedback.
• Participants' spatial (SWM), verbal, and rotation (RWM) working memory capacities were assessed.
• Dopamine-related genetic profiles were analyzed for associations with task performance.

Main Results:

• Higher SWM was significantly associated with greater success and improved reproduction of motor actions.
• Higher RWM predicted the use of explicit strategies during motor adjustments.
• No significant association was found between dopamine-related genotypes and motor task performance.

Conclusions:

• Domain-specific working memory capacity, particularly SWM, is a pivotal predictor of individual success in reward-based motor learning.
• The findings highlight a dissociable role for SWM and RWM in different aspects of reward-based motor learning.
• Contrary to expectations, dopamine genetics did not influence performance, suggesting working memory is a primary determinant.