Working memory load increases movement-related alpha and beta desynchronization.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Motor Control

Background:

• Working memory (WM) load is known to impair attention and inhibition.
• Its impact on motor function, particularly force control, is less understood.
• Investigating WM load's effect on motor control is crucial for a comprehensive understanding of cognitive-motor interactions.

Purpose of the Study:

• To examine how working memory (WM) load influences static force control.
• To investigate the effects of WM load on movement-related brain activity, specifically alpha and beta event-related desynchronization (ERD).
• To explore the compensatory mechanisms in sensorimotor cortical activity under cognitive load.

Main Methods:

• Sixteen healthy young adults performed a static force matching task with varying WM loads (low vs. high).
• Force control precision was manipulated using visual gain (low vs. high).
• Electroencephalography (EEG) recorded central brain activity (alpha and beta ERD), alongside force accuracy and steadiness.

Main Results:

• Force accuracy and steadiness improved with higher visual gain, but were unaffected by WM load.
• Alpha and beta ERD increased significantly with higher visual gain and higher WM load.
• Higher WM load led to greater sensorimotor cortical activity.

Conclusions:

• Increased WM load prompts compensatory activation in sensorimotor cortical areas in young adults.
• This neural compensation helps maintain static force control performance despite cognitive demands.
• The study provides novel insights into how WM load modulates movement-related brain activity and sensorimotor processes.