Multimodal Neuroimaging Using Concurrent EEG/fNIRS for Poststroke Recovery Assessment: An Exploratory Study

Area of Science:

• Neuroscience
• Biomedical Engineering
• Rehabilitation Science

Background:

• Persistent motor deficits are a significant cause of disability in stroke survivors.
• Current clinical assessments of motor recovery lack precision and objectivity.

Purpose of the Study:

• To develop and validate a multimodal neuroimaging approach for identifying biomarkers of motor recovery.
• To document cortical reorganization in post-stroke patients using concurrent electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS).

Main Methods:

• Simultaneous EEG and fNIRS data were collected during a hand-clenching task in 9 healthy controls and 18 stroke patients.
• A novel fNIRS-informed EEG source imaging method estimated cortical activity and functional connectivity.
• Graph theory analysis identified network features for monitoring and predicting motor function recovery over a 4-week intervention.

Main Results:

• Stroke patients exhibited lower task-evoked activity in the ipsilesional primary somatosensory cortex compared to controls.
• Increased activity in the ipsilesional premotor cortex and connectivity between motor cortices correlated with motor function improvement.
• Baseline activity in the ipsilesional premotor cortex predicted better recovery, while connectivity between SMA-M1 indicated poorer recovery.

Conclusions:

• The multimodal EEG/fNIRS technique shows potential for objective monitoring and prediction of post-stroke motor recovery.
• Further validation in larger studies is warranted to confirm these preliminary findings.