Abstract: Objective To observe the character of amplitude of myoelectric activity with surface electromyography (sEMG) on pharyngeal swallowing in healthy middle-aged and elderly people. Methods From January, 2015 to January, 2016, 78 healthy subjects were separated into middle-aged group (38~60 years old, n=38) and elderly group (61~82 years old, n=40). The amplitudes of sEMG activity of related muscles under different swallowing modes were recorded by sEMG technique and analysis system. The root mean square (RMS) was analyzed. Results There was significant difference in RMS among different swallowing modes (F>105.120, P<0.001). There was no difference in RMS between two muscles under all the swallowing modes in both groups (t<1.135, P>0.05). There was no difference between two groups in both muscles under relax and dry swallow (t<1.412, P>0.05), and was different under water swallow and continuous drinking (t> 2.700, P<0.05). Conclusion sEMG could be used for analyzing the characteristics of amplitude of myoelectric activity in healthy middle- aged and elderly people during pharyngeal swallowing in different swallowing modes, that can be used to evaluate and screen swallowing and dysphagia in clinic.

Key words: swallowing function, surface electromyography, root mean square, time-domain measures, middle aged, old