Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation

Summer 2015

Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Communication Sciences and Disorders


Christy Ludlow

Rory A. DePaolis


Singers need to counteract respiratory elastic recoil at high and low lung volume levels (LVLs) to maintain consistent airflow and pressure while singing. Professionally trained singers modify their vocal and respiratory systems creating a physiologically stable and perceptually pleasing voice quality at varying LVLs. In manuscript 1, we compared non-singers and singers on the initiation of a voiceless plosive followed by a vowel at low (30% vital capacity, VC), intermediate (50%VC), and high (80%VC) LVLs. In manuscript 2, we examined how vocal students (singers in manuscript 1) learn to control their voice onset at varying LVLs before and after a semester of voice training within a university program. Also examined were the effects of training level and LVLs on cortical activation patterns between non-singers and singers (manuscript 1), and within vocal students before and after training (manuscript 2) using fNIRS. Results revealed decreased control of voice onset initially in singers prior to training as compared to non-singers, but significant improvements in initial voice onset control after training, although task difficulty continued to alter voice physiology throughout. Cortical activation patterns did not change with training but continued to show increased activation during the most difficult tasks, which was more pronounced after training. Professionally trained techniques for consistent, coordinated voice initiation were shown to alter voice onset following plosive consonants with training. However, in non-singers and, as performance improved in singers after training, cortical activation remained greatest during the tasks at low LVLs when difficulty was highest.



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