The self-recording audiometer which was introduced by Georg von Bekesy in 1947 has already become indispensable in diagnostic audiology. It records automatically those threshold excursion tracing from just audible to just inaudible under control by the listner responding to the test tone.
The statistical study was made with the self-recording audiograms which were taken from the normal young Koreans, aged 20-30 with no E.N.T. troubles showing the hearing level below 15 dB on each frequencies such as 500, 1000, 2000, 4000,& 8000 Hz. The audiogram was made by the continuous varying frequency tracing and the fixed frequency tracing with the Automatic Self-recording Audiometer, type A-60-A, of R. Nagashima Medical-Instrument Co. Ltd.
It was at first traced with the continuous varying frequency for 10 minutes from 200 Hz to 10, 000 Hz, and next done with the fixed frequency for 3 minutes at each frequencies of 500, 1000, 2000, 4000 & 8000 Hz.
The mean and median value of excursion numbers and excursion width as a whole (Tab.1) and of each sections (Tab-2) were calculated from the audiograms of the continuous tracings for 10 minutes. And calculated the mean and median value of excursion numbers (Ttb.3) and ofe xcursion width(Tab.4)at each frequency under the fixed frequency tracing for 3 minutes each.
The differential relations between male and female were also studied showing similarity to each other.
This study showed the tendency decreasing slightly in excursion width from low to high frequency levels and increasing slightly the number of excursions, especially around 4000 Hz.
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