Intraoral pressures produced by thirteen semi-occluded vocal tract gestures

The use of semi-occluded vocal tract (SOVT) exercises as habilitative and rehabilitative tools has grown substantially in the past two decades. As the use of these exercises has grown, so too has the number of variations of the phonatory gestures used to create oral semi-occlusions. While much of the research on SOVT exercises to this point has been conducted using straw phonation, there has been little discussion or investigation regarding how other phonatory gestures that are considered to be SOVT compare to one another. The current study sought to measure the intraoral pressure produced by 13 phonatory gestures generally thought of as oral semi-occlusions. Twenty subjects (10 male, 10 female) produced three tokens of each gesture, and intraoral pressure was recorded via a thin, flexible-cannula pressure transducer. Pressures ranged between 0.1 and 1.0 kPa, but varied significantly between gestures and between subjects.