Learning and recall of incremental kinematic and dynamic sensorimotor transformations

Area of Science:

• Neuroscience
• Motor Control
• Human Movement Science

Background:

• Sensorimotor adaptation typically involves learning from significant movement errors.
• Previous research indicates robust learning and recall following sudden sensorimotor transformations.

Purpose of the Study:

• To investigate if learning and retention of sensorimotor transformations occur without large movement errors.
• To compare learning and retention between incremental and instantaneous introduction of kinematic and dynamic perturbations.

Main Methods:

• Participants adapted reaching movements to either a visuomotor rotation (kinematic) or a viscous force field (dynamic).
• Perturbations were introduced incrementally or instantaneously.
• Learning retention was assessed by re-testing participants 24 hours later.

Main Results:

• Participants in both instantaneous and incremental groups showed retention of learning across days.
• Incremental introduction of perturbations resulted in equal or better retention compared to instantaneous introduction for both kinematic and dynamic transformations.
• Significant learning and retention were observed even when participants did not experience large movement errors.

Conclusions:

• Large movement errors are not essential for the learning and retention of internal models for sensorimotor transformations.
• Incremental adaptation strategies can be as effective, or more effective, for long-term retention of sensorimotor learning.
• Findings challenge the necessity of error-based learning mechanisms in sensorimotor adaptation.