Surface electromyographic activity of non-laryngeal neck muscles in Cantonese tone production

Patients after laryngectomy lose the ability of speaking. Electrolarynx is a commonly used electronic device that helps these patients to communicate using speech. Existing electrolarynx systems do not provide pitch control function, which is critical to speech communication, especially for tonal languages. This study investigated the surface electromyographic (sEMG) activity of non-laryngeal neck muscles in producing speech sounds with different pitch. In particular, the sEMG signals for producing different lexical tones of Cantonese were analyzed. It was found that the sEMG signals measured from the sternocleidomastoid muscle could be used to indicate the pitch level of voice. Cantonese words with high-pitch tones could be distinguished from those with low-pitch tones based on the sEMG signals. This finding reveals the possibility of using sEMG for pitch control of electrolarynx systems.