Voice onset time in Parkinson disease

by Budkowski, Emily.

Abstract (Summary)
Dr. Alexander Goberman, Advisor Research examining Voice Onset Time (VOT) in individuals with Parkinson Disease (PD) has shown mixed results. Some research has shown longer VOTs, some have found shorter VOTs, while others have found a similar VOT between individuals with PD and controls. Previous research in non-neurologically impaired individuals has found that changes in speaking rate have an effect on VOT. Given that individuals with PD are known to exhibit speaking rate differences compared to controls, the current study examined VOT in individuals with PD based on two different measures: (1) the conventional VOT measure (VOT); and (2) VOT with the effect of rate removed (VOT Ratio). Results indicated a significant effect of place of articulation for voiceless sounds and a significant vowel height effect for the VOT ratio of voiceless sounds. Results indicated that there were no significant differences between the PD groups compared to controls for both VOT and VOT ratio. Within the PD group, levodopa appeared to have a greater effect on VOT than VOT ratio, meaning that the difference was actually more reflective of a medication-related rate change, rather than a pure VOT change. Overall, the current data support the usefulness of examining both VOT and VOT ratio with individuals with PD, as this method allows for dissociation between rate-related changes and true VOT-related changes. iii
Bibliographical Information:


School:Bowling Green State University

School Location:USA - Ohio

Source Type:Master's Thesis

Keywords:articulation disorders parkinson s disease


Date of Publication:

© 2009 All Rights Reserved.