Date of Award

Spring 1-1-2017

Document Type


Degree Name

Master of Arts (MA)

First Advisor

Neeraja Sadagopan

Second Advisor

Jen Lewon

Third Advisor

Pui Fong Kan

Fourth Advisor

Kenneth Wright


Sleep deprivation has been shown as detrimental to several cognitive functions and a predisposing agent to various undesirable health outcomes. Related to communication, sleep deprivation has been briefly explored with vocal function being the major research focus of the speech subsystems. This study aimed to investigate (a) the acoustic changes in participant voices as a function of sleep deprivation and (b) any subjectively perceivable changes in those same voices. Eleven subjects participated in a sleep deprivation study of 18 hours of sustained wakefulness. Six repeated nonwords served as the speech stimuli. Fifteen listeners perceptually rated the voices of these subjects. It was hypothesized that (a) there would be changes in the acoustic measures of subject voices with sleep deprivation indicating a detrimental effect and (b) voices would be rated lower on several perceptual parameters with sleep deprivation. There were few statistically significant results, but the acoustic variables that were significant suggested improvements to vocal functioning rather than detriment based on average shimmer and average harmonics-to-noise ratio. Listener ratings of the voices were variable. Future research on this topic is recommended to clarify and further support outcomes in the existing literature, as well as to offer insight into any connection between sleep disorders and voice disorders characteristic of several etiologies within the scope of practice of speech-language pathology.