An electrophysiological investigation of deglutition in man.

This article describes a combined electrophysiological and mechanical method used to measure laryngeal movements and related submental EMG activity during swallowing. The mechanical upward and downward movements of the larynx were detected using a piezoelectric sensor while the submental integrated EMG (SM-EMG) was recorded. Measurements were performed in 29 human subjects. The interval between the onsets of the two sensor signal deflections was used as a measure of the time the larynx remained in its superior position during swallowing. In 10 subjects, the cricopharyngeus muscle (CP) of the upper esophageal spinchter showed a continuous tonic EMG activity except during swallowing. All the parameters measured were influenced by the type and volume of the bolus material. The method presented in this study proved its usefulness in the study of the physiology of deglutition as well as in its objective clinical evaluation in patients with dysphagia.