title: Dynamics of posterior tongue during pronunciation and voluntary tongue lift movement in young adults.
abstract: The lifting-up movement of the posterior part of the tongue to touch the palate, which is a requirement for performing physiological functions such as deglutition and speech, is an important phenomenon that is difficult to objectively evaluate. The purpose of this study was to develop a new modality to evaluate the tongue-lifting function, especially in the posterior part of the tongue, and to elucidate the dynamic properties of the tongue in normal subjects. Twenty-three healthy volunteers (9 men and 14 women; mean age, 27·6years) participated in this study. A new device was developed that could evaluate the up-down movement of the posterior part of the tongue in a non-invasive manner. The experimental tasks were as follows: (i) /a/ pronunciation for 1s followed by /ka/ pronunciation (a-ka task), (ii) /a/ pronunciation for 1s followed by /ga/ pronunciation (a-ga task) and (iii) /a/ pronunciation for 1s followed by a voluntary push-up movement of the posterior part of the tongue (a-lift task). Maximum upward velocity in the a-ga task was larger than that in the a-ka task (P<0·05). The a-lift task showed the highest tongue lift range among the three tasks, and the a-ga task showed a higher range than that of the a-ka task (P<0·05). This study revealed that precise quantification of the motility of the posterior part of the tongue, which would be useful in rehabilitation of articulation and/or swallowing, could be achieved using this new device in a non-invasive manner.
authors.affiliation: Department of Occlusal and Oral Functional Rehabilitation, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Shirahige
authors.forename: K
authors.initials: K
authors.lastname: Oki
authors.forename: Y
authors.initials: Y
authors.lastname: Morimoto
authors.forename: N
authors.initials: N
authors.lastname: Oisaka
authors.forename: S
authors.initials: S
authors.lastname: Minagi
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement; D010700:Phonetics; D013060:Speech / Q000502:physiology*; D013062:Speech Articulation Tests / Q000295:instrumentation*; D014059:Tongue / Q000502:physiology*