Associative cued asynchronous BCI induces cortical plasticity in stroke patients.

Area of Science:

• Neuroscience
• Biomedical Engineering
• Rehabilitation Technology

Background:

• Brain-computer interfaces (BCIs) offer potential for neuromodulation and motor rehabilitation.
• Existing asynchronous BCIs face challenges with accuracy and false positives.
• Targeting motor cortical activity with somatosensory feedback is a promising strategy for enhancing neural plasticity.

Purpose of the Study:

• To introduce and evaluate a novel cue-based asynchronous BCI system for neuromodulation.
• To compare the performance of the cue-based asynchronous BCI against traditional BCI modes and a control intervention.
• To assess the impact of the BCI interventions on corticomotor excitability in chronic stroke patients.

Main Methods:

• A cue-based asynchronous BCI was developed, detecting movement intention from EEG signals during cued intervals.
• Chronic stroke patients performed paretic limb movements under the novel BCI, traditional asynchronous BCI, offline synchronous BCI, and control conditions.
• Corticomotor excitability was measured using motor-evoked potentials (MEPs) via transcranial magnetic stimulation (TMS) before, immediately after, and 30 minutes post-intervention.

Main Results:

• The cue-based asynchronous BCI demonstrated significantly fewer false positives compared to the standard asynchronous BCI.
• All BCI interventions led to increased MEP amplitudes immediately post-intervention compared to the control group.
• The novel cue-based asynchronous BCI achieved the greatest increase in MEP amplitudes (141%) and sustained this effect for 30 minutes.

Conclusions:

• The proposed cue-based asynchronous BCI is a high-performance system for neuromodulation.
• This BCI paradigm effectively pairs volitional brain activity with sensory stimulation for enhanced plasticity induction.
• The findings support the use of cue-based asynchronous BCIs for improving motor function and rehabilitation outcomes.