Temporal structure of motor variability is dynamically regulated and predicts motor learning ability

Area of Science:

• Neuroscience
• Motor Control
• Cognitive Science

Background:

• Individual differences in motor learning are significant.
• The underlying factors driving these differences remain largely unknown.
• Movement variability is a common characteristic of motor performance.

Purpose of the Study:

• To investigate the relationship between motor output variability and motor learning ability.
• To determine if task-relevant motor variability predicts learning speed.
• To explore if motor variability can be modulated by training.

Main Methods:

• Two distinct learning paradigms were employed: reward-based learning for arm trajectories and error-based learning for adaptation in novel environments.
• Motor output variability was measured across individuals and tasks.
• The temporal structure of motor variability was analyzed before and after training.

Main Results:

• Increased task-relevant motor variability was correlated with faster motor learning across both individuals and tasks.
• Training successfully reshaped the temporal structure of motor variability.
• This reshaping of variability aligned with the trained task, leading to improved learning.

Conclusions:

• Motor variability is not merely noise but actively facilitates motor learning in humans.
• The nervous system strategically regulates motor variability to enhance learning.
• These findings support the role of action exploration in motor skill acquisition.