Electroencephalographic Characterization of Sensorimotor Neural Activation During Swallowing in Dysphagic Patients

Abstract

Highlights: What are the main findings? EEG analysis revealed reduced beta desynchronization in motor cortical areas of post-stroke patients. Dysphagic patients showed specific deficits in alpha/beta desynchronization at C3 and Cz and exhibited abnormal lateralization. What are the implications of the main findings? EEG-derived biomarkers allow objective discrimination between dysphagic and non-dysphagic populations. The accessibility of EEG supports its integration into clinical workflows for dysphagia diagnosis and follow-up. Dysphagia is commonly assessed with qualitative and image-based diagnostic tools, which are often costly, technically demanding, and limited in their ability to support individualized rehabilitation. Electroencephalography (EEG) has recently emerged as a quantitative, cost-effective, and accessible alternative to characterize sensorimotor activity during swallowing, though its potential in dysphagic populations has not been systematically explored. This study investigated neural dynamics in 50 post-stroke dysphagic patients, 32 post-stroke non-dysphagic controls, and 21 healthy adults performing a swallowing task. EEG recordings from primary motor regions (C3, Cz, C4) were analyzed using event-related spectral perturbation (ERSP) to quantify alpha (8–13 Hz) and beta (15–30 Hz) event-related desynchronization, alongside hemispheric lateralization indices. Group comparisons revealed significantly reduced beta desynchronization in both post-stroke groups compared to healthy participants, with additional alpha and beta deficits at C3 and Cz distinguishing dysphagic patients from non-dysphagic controls. Dysphagic patients further exhibited abnormal lateralization not observed in other groups. These findings identify distinct alterations in motor cortical dynamics and hemispheric balance in dysphagia, supporting EEG-derived biomarkers as promising tools for diagnosis and clinical follow-up. The accessibility of EEG reinforces its potential integration into routine workflows to enable objective and personalized management of post-stroke dysphagia.