Basic Characteristics of Submental Mechanomyography and Electromyography Measured Simultaneously During Tongue Lift Using a Novel Muscle Function Measurement Device

Purpose Methods and instruments that allow the simple and quantitative assessment of the swallowing function are needed. This study develops a device for the simultaneous measurement of displacement mechanomyography (dMMG) and electromyography (EMG) on the suprahyoid muscles contributing to swallowing and evaluate the characteristics of both signals during tongue lift. Methods Eleven healthy males participate in the experiment. Tongue pressure (TP) is set at six levels from 15 to 90%MVC. The participants maintained each load level for 5 s and measured dMMG, EMG, and TP. The parameters were analyzed in the time- and frequency-domains. Reliability is assessed by the intra-class correlation coefficient (ICC) and coefficient of variation (CV). Results Excellent intra-session reliability of dMMG and EMG was observed for all tasks (ICC: 0.82–0.98), and CV was close to or below 10%. EMG increased progressively with increasing contraction intensity, but dMMG increased significantly up to 60%MVC and then plateaued. In the frequency-domain, most powers in dMMG and TP were