UMD Theses and Dissertations

Permanent URI for this collectionhttp://hdl.handle.net/1903/3

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a given thesis/dissertation in DRUM.

More information is available at Theses and Dissertations at University of Maryland Libraries.

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Subject: search.filters.subject.Hearing Loss

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    Temporary Changes in Auditory Function Among College Marching Band Members
    (2008-04-18) Libbin, Barbara; Gordon-Salant, Sandra; Hearing and Speech Sciences; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The purpose of this study was to evaluate temporary changes in auditory function associated with marching band practice among college-aged marching band participants. Each eligible musician was tested before and after two practices in the time span of one week. Sound level recordings at a location close to the center of the marching band were documented to be 85 - 105 dB(A), with peaks measured at 114 dB(A). Pure-tone thresholds and transient evoked (TEOAE) and distortion product (DPOAE) otoacoustic emissions were tested to evaluate if any changes occurred as a result of the marching band practices. If clinically significant changes were noted from pre- to post-practice testing, the band member returned the following morning to evaluate if any recovery had occurred. The principal finding was a significant effect of test time (pre versus post-practice), which was observed in the pure-tone data (3000, 4000, 6000 and 8000 Hz), DPOAE data (3000 Hz, left ear only) and TEOAE data (narrowband and broadband) in the marching band group. For those participants who showed clinically significant changes in auditory function, these changes were found to recover by the next morning. The results suggest that the measured changes in this study are temporary in nature; however, they might be an early indication of future permanent changes. Comparison of data from the marching band members and the control group participants revealed a significant difference between the groups in two measures: pure-tone thresholds at 8000 Hz and TEOAEs (broadband and narrowband). Overall, participation in the two-hour, outdoor marching band practice was not found to be more detrimental to auditory functioning than everyday noise exposure. However, there is evidence that exposure to marching band music produces subtle changes in auditory functioning, particularly as measured with pure-tone thresholds and TEOAEs.
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    Perceptual Consequences of Early-Onset Hereditary Hearing Loss in the Belgian Waterslager Canary (Serinus Canarius)
    (2006-05-30) Lauer, Amanda M; Dooling, Robert J; Psychology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Belgian Waterslager canaries (BWS) are bred for a distinctive low-pitched song that includes sounds that are thought to resemble water. This strain of canary has been used in multiple neurobiological and behavioral studies of song learning. These birds have a permanent hereditary hearing loss associated with missing and abnormal hair cells. The hearing deficit develops after hatch, but is present when the birds learn their song. The manner in which these birds process complex sounds indisputably affects the content of their vocalizations; however, no studies have looked at BWS canaries' ability to detect and discriminate sounds other than detection of pure tones in quiet. Thus, the BWS canary provides a unique opportunity to investigate the relationship between the form and function of an auditory system involved in vocal learning. Here I describe a series of psychoacoustic experiments that investigate differences in masking, discrimination, temporal processing, and perception of song elements in BWS canaries and normal-hearing non-BWS canary strains. Spectral and temporal studies of masking showed that frequency resolution and the phase response of the basilar papilla are impaired in BWS canaries. Frequency discrimination was superb at low frequencies, but worse than normal at high frequencies in BWS canaries. Duration and intensity discrimination was not adversely affected by the hearing loss. Temporal resolution was normal or better than normal under some conditions in BWS canaries. Despite the hearing loss, BWS canaries are able to accurately discriminate among strain-specific song syllables as well as syllables of other canary strains. In fact, BWS canaries are actually better than non-BWS canaries at discriminating among BWS canary syllables. These perceptual predispositions in BWS canaries are presumably related to the structural abnormalities of the inner ear, and are likely to play a role in song learning and song maintanence by enhancing the birds' ability to attend to important acoustic features that are characteristic of BWS vocalizations.