Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 153-159).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1949. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [89]-90).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1963. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 104-110).

Thesis (M.S.)--University of Wisconsin--Madison, 1971. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

No description available.

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xi, 102 p. : ill. (some col.). Advisor: Lawrence Feth, Dept. of Speech & Hearing Science. Includes bibliographical references (p. 97-102).

Thesis (M. S.)--Psychology, Georgia Institute of Technology, 2007. / Corso, Gregory, Committee Member ; Davis, Elizabeth, Committee Member ; Walker, Bruce, Committee Chair.

Virtual three-dimensional (3D) auditory displays utilize signal-processing techniques to alter sounds presented through headphones so that they seem to originate from specific spatial locations around the listener. In some circumstances bone-conduction headsets (bonephones) can provide an alternative sound presentation mechanism. However, existing 3D audio rendering algorithms need to be adjusted to use bonephones rather than headphones. This study provided anchor points for a function of shift values that could be used to adapt virtual 3D auditory displays for use with bonephones. The shift values were established by having participants adjust phase and amplitude of two waves in order to cancel out the signal and thus produce silence. These adjustments occurred in a listening environment consisting of air-conducted and bone-conducted tones, as well as air- conducted masking. Performance in the calibration condition suggested that participants understood the task, and could do this task with reasonable accuracy. In the bone-to-air listening conditions, the data produced a clear set of anchor points for an amplitude shift function. The data did not reveal, however, anchor points for a phase shift function the data for phase were highly variable and inconsistent. Application of shifts, as well as future research to establish full functions and better understand phase are discussed, in addition to validation and follow-up studies.

Virtual three-dimensional auditory displays (V3DADs) use digital signal processing to deliver sounds (typically through headphones) that seem to originate from specific external spatial locations. This set of studies investigates the delivery of V3DADs through bone-conduction transducers (BCTs) in addition to conventional headphones. Although previous research has shown that spatial separation can be induced through BCTs, some additional signal adjustments are required for optimization of V3DADs, due to the difference in hearing pathways. The present studies tested a bone-conduction adjustment function (BAF) derived from equal-loudness judgments on pure tones whose frequencies were spaced one critical band apart. Localization performance was assessed through conventional air-conduction headphones, BCTs with only transducer correction, and BCTs with a BAF. The results showed that in the elevation plane, the BAF was effective in restoring the spectral cues altered by the bone-conduction pathway. No evidence for increased percept variability or decreased lateralization in the bone-conduction conditions was found. These findings indicate that a V3DAD can be implemented on a BCT and that a BAF will improve performance, but that there is an apparent performance cost that cannot be addressed with BAFs measured using the methodology in the present studies.

Speech reception threshold testing by bone conduction is very useful in diagnostic audiometry. However, there are little data regarding the CID W-1 spondee word lists used with the Radioear B-71 and B-72 and Pracitronic KH 70 bone conduction vibrators at higher presentation levels for testing hearing impaired clients. Data are needed in order that results of speech reception thresholds using the CID W-1 word lists via these three bone conduction vibrators at higher intensity levels can be used confidently in the clinic. More data are available for speech reception thresholds using the CID W-1 word lists via earphones. This study compared speech intelligibility presented via bone conduction at higher intensity levels to that presented via earphone at higher intensity levels. Twelve normal hearing adults, with thresholds artificially elevated by binaural speech noise masking to simulate a hearing impairment, were used as subjects. Recorded CID W-1 spondee word lists were presented via four transducers: Radioear B-71, Radioear B-72, and Pracitronic KR 70 bone vibrators, and a TDH-39 earphone. Investigation of each bone conduction vibrator was accomplished by using forehead placement and using binaural speech noise masking via earphones. Investigation of the earphone was accomplished by simultaneously presenting binaural speech stimuli and speech noise masking. Spondees from the CID W-1 word lists were presented to the subject via a transducer. A bracketing technique was used to estimate the speech reception threshold. Using the intensity level of the predetermined SRT as 0 dB, each list was presented at one of the following levels: +4, +2, O, -2, -4, and -6. Performance-intensity functions, the percentage of correctly identified spondees as a function of presentation level, were obtained for each transducer. The percentage of spondees correctly identified increased with the stimulus level for all transducers. Using linear regression, the line of best fit was calculated for each subject's data under each transducer condition. A one way analysis of variance indicated that there was a significant difference in the slopes of the performance-intensity functions of the transducers. A follow-up test for the one way analysis of variance indicated that there was a signficant difference between the TDH-39 earphone and each of the bone conduction vibrators. There were no significant differences among the bone conduction vibrators. Results of the study suggested that CID W-1 word lists and the 50 percent criterion may be inappropriate for use with these bone conduction vibrators at higher intensity levels. Given that there was a preponderance of data points below 50 percent for the bone vibrators, a criterion of less than 50 percent might be more appropriate. Because presentation levels might be elevated for sensorineural hearing impaired listeners, their SRT performances could be affected. Consequently, the results of speech reception threshold testing via bone conduction at higher intensity levels should be interpreted with caution in clinics.