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

Spring 2015

Document Type


Degree Name

Doctor of Audiology (AuD)


Department of Communication Sciences and Disorders


Ayasakanta Rout


The most common type and configuration of hearing loss seen in clinics is high frequency sensorineural hearing loss. High-frequency hearing losses can lead to difficulties understanding speech in noise. Traditional amplification can aid in audibility of high-frequency information; however, its success is limited due to acoustic feedback, output limitations of the hearing aids, and loudness discomfort (Bohnert, Nyffeler, & Keilmann, 2010, Turner & Cummings, 1999). Cochlear dead regions further hinder the success of traditional hearing aids, as speech recognition may not improve with increased audibility (Turner & Cummings, 1999). Frequency-lowering algorithms, developed by four major hearing aid manufacturers, attempt to provide improved audibility and speech understanding. Several studies have assessed the success of this technology; however mixed results have been found. The current study’s purpose is to examine the effects of adaptive frequency lowering on phoneme identification and sound quality of music. Seven subjects with high frequency hearing loss were fit with Starkey Xino RITE hearing aids and were tested in two conditions (adaptive frequency lowering on and adaptive frequency lowering off). The Nonsense Syllable Test, Speech Perception In Noise test, and sound quality of music forced choice protocol were used to compare the two algorithms. The results of this study revealed no significant differences between traditional amplification and adaptive frequency lowering algorithm for identification of nonsense syllables, speech perception in noise, and preference of sound quality of music.



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