Date of Award

Fall 2014

Degree Type


Degree Name

Master of Science (MS)


Agricultural and Biological Engineering

First Advisor

Jessica E. Huber

Committee Member 1

Preeti Sivasankar

Committee Member 2

Barbara SW Solomon


Teachers use their voice as a key part of their profession, often speaking at an increased loudness for multiple hours a day. This places teachers at a high risk for voice disorders, which costs the United States billions of dollars annually. Vocal fatigue, or worsening of the voice as the day progresses, is a common complaint from teachers. The present study investigated respiratory and laryngeal function in teachers pre and post a 1-hour vocal loading challenge. Six teachers and three student teachers (total of 9 subjects) produced four speech tasks and completed two perceptual ratings pre and post a 1-hour reading aloud vocal loading challenge in 70 dB multi-talker babble. Dependent variables included vocal tiredness and vocal effort ratings, cepstral peak prominence (CPP), low/high spectral ratio (L/H ratio), sound pressure level (SPL), utterance length (# of syllables), percent vital capacity expended per syllable (%VC/syllable), and lung volume initiation (%LVI-EEL), termination (%LVT-EEL), and excursion (%LVE). Following the vocal loading challenge, utterance length and SPL significantly increased, and %VC/syllable significantly decreased. %LVI-EEL increased post-vocal loading challenge, but it did not reach statistical significance. No laryngeal differences were found. These results suggest that subjects altered the respiratory system for three possible scenarios: to overcome perceived increase in difficulties for speech, to plan for longer utterances, or to overcome hyperventilation caused by the 1-hour vocal loading challenge.