A pilot study of high-density electromyographic maps of muscle activity in normal deglutition

While various methods have been used to study physiological aspects of swallowing, few studies have been conducted to investigate the dynamics of a swallowing procedure with the activation pattern of swallowing muscles. In this pilot study we investigated the feasibility of surface electromyographic (sEMG) dynamic topography as a new approach for continuously visualizing muscle activity of normal swallowing. The dynamic sEMG topographies (or potential mappings) of swallowing were constructed with high-density sEMG recordings from three subjects without any swallowing disorders. The root mean square (RMS) of the sEMG signals was calculated as a function of both position and time to produce two-dimension dynamic sEMG maps of the muscle activity during swallowing. The sEMG maps could provide the information about the dynamic characteristics of swallowing muscles, which is accordance with physiological and biomechanical laws of a normal swallowing. With the results of the present study, we might conclude that the dynamic topography would provide a noninvasive means to continuously visualize the distribution of surface EMG signals of complex muscle activities of normal deglutition.