Environmental consistency modulation of error sensitivity during motor adaptation is explicitly controlled

Area of Science:

• Neuroscience
• Motor Control
• Cognitive Psychology

Background:

• Motor adaptation adjusts motor output to environmental changes.
• Error sensitivity modulation was traditionally viewed as implicit, but explicit strategies may contribute.
• The role of explicit vs. implicit processes in consistency-driven adaptation is unclear.

Purpose of the Study:

• To investigate whether explicit control influences error sensitivity modulation during sensorimotor adaptation.
• To differentiate the contributions of explicit and implicit processes to adaptation rate changes under varying environmental consistency.

Main Methods:

• Participants controlled a screen cursor to virtual targets under different environmental consistency conditions (random vs. random walk perturbations).
• Explicit strategy contribution was manipulated by instructing participants to ignore cursor feedback.
• Implicit learning was modulated by delaying visual feedback.

Main Results:

• Perturbation consistency significantly affected the rate of motor adaptation, confirming previous findings.
• When explicit strategies were eliminated, consistency-driven error sensitivity modulation was absent.
• Delaying visual feedback did not alter error sensitivity under consistent perturbations.

Conclusions:

• Increases in learning rate associated with consistent environments are primarily mediated by explicit control.
• Implicit processes do not appear to be the main driver of consistency-based error sensitivity modulation in sensorimotor adaptation.
• Sensorimotor adaptation's response to perturbation consistency relies heavily on explicit cognitive strategies.