Event-Related Beta EEG Changes Induced by Various Neuromuscular Electrical Stimulation: A Pilot Study

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomedical Engineering

Background:

• Neuromuscular electrical stimulation (NMES) influences central and peripheral nervous system activity.
• Understanding NMES-induced cortical activity differences is crucial for optimizing motor function recovery.
• Previous studies focused on NMES-induced movement variations, leaving stimulation-specific cortical responses unclear.

Purpose of the Study:

• To investigate whether different NMES configurations elicit distinct cortical activity when producing the same peripheral movement.
• To compare the effects of four NMES configurations on sensorimotor cortical activity.

Main Methods:

• Four NMES configurations (Eight-let Frequency Trains, Doublet Frequency Trains (DFT), narrow-pulse Constant-Frequency Trains, wide-pulse Constant-Frequency Trains) were applied to the biceps brachii in healthy adults.
• Stimulation intensities were adjusted to achieve consistent elbow flexion across configurations.
• Cortical activity over sensorimotor regions was measured and compared.

Main Results:

• All four NMES patterns induced different beta-band Event-Related Desynchronization (ERD).
• Doublet Frequency Trains (DFT) resulted in significantly stronger beta-band ERD compared to other configurations for the same induced elbow flexion (p < 0.05).
• Observed differences in ERD may stem from varying activation of afferent proprioceptive fibers by different NMES configurations.

Conclusions:

• NMES configuration significantly influences beta-band ERD, even when evoking identical movements.
• DFT configuration appears most effective in generating cortical changes.
• NMES-induced beta-band ERD should be considered when selecting configurations for enhanced motor function recovery.