Anna Tignor, Tepanta Fossett, Ph.D.

Lee Silverman Voice Treatment and Parkinson’s Disease

View the poster >>

Abstract:

Parkinson’s disease is a progressive neurological disorder that affects the nervous system and parts of the body controlled by these nerves. Hypokinetic dysarthria is a motor speech disorder characterized by reduced vocal loudness, imprecise articulation, breathiness, short bursts of speech, irregular pauses, and monotone voice. One well supported treatment for this type of dysarthria seen in individuals with PD is the Lee Silverman Voice Treatment (LSVT). LSVT is an intensive four-week program of voice therapy targeting hypokinetic dysarthria in individuals with PD, with an overall goal of increasing vocal loudness so these individuals can improve their communication with conversation partners. Typical speech-language treatment in PD focuses on maintaining as much communication ability as possible including strategies and exercises to help with volume and speed of speech, breathing, facial expressions, and articulation. The purpose of this research investigation is to compare LSVT and typical speech-language treatment in improving functional communication outcomes for individuals with PD, or ability to use compensatory strategies to participate fully and competently in conversations. Results will be investigated through quality-of-life, quantitative, and perceptual measures. 

50 individuals with PD will be randomly assigned to two groups, with one group receiving LSVT and the other group receiving typical speech-language treatment. The dependent measures for this investigation will be administered before, during, and after treatment over a span of four weeks. To measure functional communication, the Voice Handicap Index (VHI) and the Communicative Effectiveness Survey (CES) will be administered. These questionnaires allow participants to describe their voice and communication and the effects these facts have on their lives. Quantitative measures will consist of measures of vocal loudness obtained from three tasks using a sound pressure level (in decibels): 1) sustained /a/ phonation, 2) reading of a passage, and 3) connected speech with a self-chosen monologue. Additional quantitative data will be provided by measuring articulatory rate, calculated by measuring the length of each syllable produced and the pause at the end and within words. Perceptual data will be obtained from the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) and will provide information regarding six vocal qualities: 1) overall severity, 2) roughness, 3) breathiness, 4) strain, 5) pitch, and 6) loudness. In conjunction with the quality-of-life measures, these quantitative and perceptual measures will be identified and used in comparison among the two groups. Finally, to measure speech intelligibility, the Assessment for the Intelligibility of Dysarthric Speech will be administered to obtain an overall severity estimate of dysarthria in the individuals with PD.

It is hypothesized that LSVT will reduce the effects of PD on communication and positively affect speech intelligibility and vocal quality. Results will have implications for identifying and forming an effective treatment plan in individuals with PD with an overall goal of improving functional communication. In this between-subjects research design, my research proposal targets the efficacy of LSVT in PD. This research will identify if LSVT, when compared to typical speech- language treatment, results in significant differences on vocal loudness, phonation, articulatory rate, and functional communication outcomes in individuals with PD.