EMG- Versus EEG-Triggered Electrical Stimulation for Inducing Corticospinal Plasticity.

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomedical Engineering

Background:

• Brain-computer interfaces (BCIs) using electroencephalography (EEG) are explored for stroke rehabilitation.
• Residual muscle (electromyography - EMG) control is common in stroke survivors, potentially making EEG unnecessary.
• Electrical nerve stimulation can induce neuroplasticity.

Purpose of the Study:

• To directly compare the efficacy of EEG- versus EMG-controlled electrical nerve stimulation in inducing corticospinal plasticity.
• To determine if EMG is a suitable alternative to EEG for triggering stimulation in stroke rehabilitation.

Main Methods:

• Twenty healthy participants underwent two intervention sessions: EEG-controlled and EMG-controlled electrical nerve stimulation.
• Each session involved 50 pairings of foot dorsiflexion movements (decoded via EEG or EMG) with common peroneal nerve stimulation.
• Transcranial magnetic stimulation (TMS) was used to elicit motor evoked potentials (MEPs) in the tibialis anterior muscle before, immediately after, and 30 minutes after interventions.

Main Results:

• Both EEG- and EMG-controlled stimulation significantly increased MEP amplitudes immediately after and 30 minutes post-intervention compared to baseline.
• No significant difference in corticospinal plasticity induction was found between EEG- and EMG-controlled stimulation.
• Observed increases in MEPs were substantial (e.g., 62-73% immediately after, 72-79% after 30 minutes).

Conclusions:

• Both EEG- and EMG-controlled electrical nerve stimulation are effective in inducing corticospinal plasticity.
• Stroke patients with residual EMG control can utilize EMG to trigger nerve stimulation for rehabilitation, offering an alternative to EEG.
• This finding supports the use of EMG-based BCIs for stroke rehabilitation, accommodating patients with varying levels of motor recovery.