Neural correlation between swallowing motor imagery and execution: An EEG analysis

Objective. The relationship between swallowing motor imagery and actual swallowing remains unclear, leading to a lack of physiological basis for the application of swallowing imagery-based brain-computer interface (BCI) paradigms in rehabilitation. This research explored the link between swallowing execution and imagery, aiming to optimize brain-computer interface applications for swallowing rehabilitation in patients with dysphagia. Approach. Thirty healthy participants performed swallowing motor imagery and saliva swallowing tasks under video cues, and Electroencephalography (EEG) signals from 64 channels and electromyographic (EMG) signals from the suprahyoid muscles were recorded. This study investigates swallowing onset detection using EMG, and explores neural dynamics during swallowing imagery and execution through EEG-based time-frequency analysis, functional connectivity analysis, and nonlinear dynamic analysis (Sample Entropy). Main results. The results revealed event-related desynchronization (ERD) in the central region (CPz, CP1-CP4) and parietal region (Pz, P1-P4) for both swallowing motor imagery and actual swallowing. Pearson’s correlation analysis indicated a weak but significant correlation (P = 0.0102). The ERD phenomenon during swallowing imagery was more similar to that during the pharyngeal stage, with a weak but significant correlation (P = 0.0139). Functional connectivity analysis revealed greater activation of the central region during swallowing imagery than during actual swallowing. In terms of sample entropy, swallowing motor execution exhibited higher signal complexity and dynamic characteristics compared to imagery. Significance. This study highlights the similarity in neural activation between swallowing imagery and execution, particularly in the central and parietal regions, supporting the application of the swallowing imagery paradigm in these regions for rehabilitation. Further research is required to enhance BCI applications in swallowing disorders.