Multi-channel study of tongue EMG during vowel production

Abstract

EMG potentials were simultaneously recorded from extrinsic tongue muscles (anterior and posterior genioglossus, hyoglossus, and styloglossus), from accessory tongue muscles (geniohyoid and mylohyoid), and from the cricothyroid and orbicularis oris superior while a single talker produced ten repetitions of 11 vowels in a /əpVp/ environment. Patterns of activity for the anterior and posterior genioglossus and for styloglossus were consistent with earlier reports. To our knowledge, hyoglossus activity has not been previously reported. This muscle demonstrated qualitatively different patterns of activity for front versus back vowels. For front vowels, an initial peak occurred simultaneously with the peak of orbicularis oris activity associated with the initial stop. This was followed by a partial suppression, the timing and extent of which was related to that of genioglossus activation. Hyoglossus activity then recovered to the level of the initial peak. For back vowels, the EMG patterns were characterized by a single peak associated with tongue positioning for the vowel. Interchannel timing relationships and their implications will be discussed. [Research supported by NINCDS.]