Reward abundance interferes with error-based learning in a visuomotor adaptation task.

Area of Science:

• Neuroscience
• Motor Control
• Cognitive Psychology

Background:

• The brain adapts reaching movements using visual error feedback.
• Reward feedback aids motor adaptation, but the mechanism is unclear.

Purpose of the Study:

• Investigate how reward abundance influences motor adaptation to errors.
• Determine if reward frequency affects learning from performance feedback.

Main Methods:

• A 3D multi-target pointing task with shifted hand-position feedback.
• Participants (N=423) received varying proportions of reward and error feedback.
• Experimental groups differed in reward abundance and feedback type.

Main Results:

• Error feedback promoted adaptation; reward feedback alone did not.
• Higher reward abundance correlated with reduced adaptation to errors.
• Abundant rewards interfered with learning from performance errors.

Conclusions:

• Reward abundance negatively impacts motor learning from errors.
• Increased reward frequency may shift reliance towards reward cues, impairing error-based adaptation.
• The brain's adaptation mechanism is sensitive to the proportion of rewarded trials.