Publication Date


Document Type


First Advisor

Rose, Darrell E.||Shearer, William M.

Degree Name

M.A. (Master of Arts)

Legacy Department

Department of Speech




This investigation was conducted to determine the effects of tonal stimulus duration on the peak amplitudes and latencies of the acoustically evoked response. Psychophysical studies have indicated a 10 dB shift in the sensitivity threshold over a decimal change in the duration time of the stimulus. It was hypothesized that this 10 dB shift in the intensity of the stimulus as the duration was decreased would be reflected by changes in the evoked response. Threshold was determined for a 1000 Hz tone of 300 msec. duration and the intensity of the stimulus was set at 40 dB SL in reference to this threshold. Responses were evoked by tones of 300, 100, 50 and 30 msec. duration. The results of this study do not support the hypothesized changes as a function of stimulus duration. The evoked response did not show a significant difference in either the amplitude or latency of the components as a function of tonal durations. In view of the results of psychophysical studies near threshold, this should be of some concern to investigators in the field of cortical audiology.


Includes bibliographical references.||Includes illustrations.


ix, 83 pages




Northern Illinois University

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