The purpose of this project is to evaluate a new therapy approach for treating hypernasal speech. Hypernasality often accompanies cleft palate, neuromotor disorders, and other impairments. It is a common communication disorder dealt with in craniofacial and speech clinics. Although many attempts have been made to reduce hypernasality therapeutically, it has been resistant to change using therapy alone. The treatment of choice for moderate-to-severe hypernasality typically is surgery, especially pharyngeal flap. Yet such surgery requires general anesthesia, and may result in mouth breathing as a postsurgical complication. The proposed therapy involves an approach that has been used to treat sleep apnea patients, continuous positive airway pressure (CPAP). The pressure delivered by a motor-tube-mask assembly to the nasal passages helps to keep the airway patent during sleep. Although not originally intended to be used during speech, the pressure delivered to the nasal passages offers a resistance to velopharyngeal closure that can be incorporated in a regimen of resistance training with principles commonly used in exercise physiology to strengthen muscles. Five subjects exhibiting moderate hypernasality will receive the therapy in an eight-week home program with six sessions per week. The nasal pressure delivered by the CPAP device and the time devoted to each session will be incremented in a stepwise fashion across the eight-week program. The initial pressure will be tailored for each subject. A multiple-probe single-subject research design will be used and the subjects will serve as their own controls. The dependent variables used to assess potential changes in hypernasality will consist of an instrumental measure, Nasometer values, and a perceptual measure, listener judgments. The proposed therapy has several advantages over previous methods: 1) the velopharyngeal mechanism is manipulated during speech production as opposed to nonspeech tasks such as swallowing and blowing, 2) the positive pressure loads the velopharyngeal mechanism thereby making use of resistance training, 3) a retrograde pressure front opposes the respiratory pressure front during speech thereby directly influencing a likely speech regulatory parameter, 4) the method is noninvasive, 5) the instrument device is easy to use, and 6) therapy can be conducted in the home thereby enabling frequent and convenient therapy sessions.
Kuehn, D P; Moon, J B (1994) Levator veli palatini muscle activity in relation to intraoral air pressure variation. J Speech Hear Res 37:1260-70 |