• 수산해양기술연구
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• 제45권4호
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• pp.260-266
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• 2009

In order to obtain the fundamental data for the marine ranch, this paper was carried out to investigate cortisol variation in blood according to adapted time in the measurement of auditory threshold. The groups were adapted at the experimental tanks for 0.5, 1, 3 and 6 hours, respectively. At the results, cortisol concentration had a deep connection with adapted time. In particular, cortisol concentration in the experimental group of 1 hour was significantly increased, whereas others showed no difference comparing with the control group. When classical conditioning method with the sound coupled with a delayed electric shock was given after the adapted time of 1 hour and 6 hours, the rate of the conditioning completion for 6 hours was higher than that of 1 hour. Therefore, this suggests that the sufficient adapted time was required for the accurate auditory threshold.

• Physical Therapy Rehabilitation Science
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• 제10권3호
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• pp.311-319
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• 2021

Objective: To investigate the effect of emphasized initial contact by using a wearable air-pressure insole to provide auditory-feedback with variations of maximum peak pressure (MPP) of the affected side on spatiotemporal gait parameters and gait symmetry of stroke patients Design: A cross-sectional study Methods: Eighteen stroke patients participated in this study. All subjects walked five trials using an air-pressure insole that provides auditory feedback with different thresholds set on the insole. First, subjects walked without any auditory feedback. Then, the MPP threshold on the affected side was set from 70% and increase threshold by 10% after each trial until 100%. They walked three times or more on the gait analyzer for each trial, and the average values were measured. Before starting the experiment, subjects measured body weight, initial gait abilities and affected side MPP without auditory feedback. Results: Temporal and spatial variables were significantly increased in trials with auditory feedback from air-pressure insole except for non-paralyzed single support time and spatial gait symmetry compared to trials without auditory feedback(p<0.05). Among the four different thresholds, the walking speed, unaffected side single support time, affected and unaffected side stride, and affected side step length were greatest at 80% threshold of maximum peak, while affected single support time, temporal gait symmetry, and unaffected step length were greatest at the maximum peak of 100% threshold. Conclusions: These results indicate that auditory feedback gait using air-pressure insoles can be an effective way to improve walking speed, single support time, step length, stride, and temporal gait symmetry in stroke patients.

• 수산해양기술연구
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• 제36권4호
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• pp.309-313
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• 2000

제주연안해역에 서식하고 있는 독가시치의 수중음에 대한 청각 특성을 파악하여 수중음을 이용한 음향 어법에 이용도를 높일 수 있는 기초자료를 제공할 목적으로 측정 주파수 80∼800Hz의 수중음과 7V의 직류 전압의 전기자극을 이용하여 음향 조건학습을 시킨 후 측정주파수와 음압을 임의로 변화시켜가면서 청각 문턱치를 구한 결과 독가시치는 측정주파수 80∼800Hz의 음을 인식하고 있었고, 측정주파수 80Hz, 100Hz, 200Hz, 300Hz, 500Hz, 800Hz에 대한 각각의 청각 문턱치는 102, 96, 92, 95, 105, 121dB로 나타났고, 측정주파수 200Hz에서 가장 낮은 음압 92dB를 나타내었으며, 측정주파수 800Hz에서 가장 높은 청각 문턱치를 나타내었다.

• 음성과학
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• 제12권2호
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• pp.81-88
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• 2005

Electrodermal activity(EDA) is a bio-electric signal which occurs at the skin surface during the sweating. EDA reflects the activity of the sympathetic axis of the autonomic nervous system. EDA is associated with the eccrine sweat gland at the palmar and plamar surface. This study was aimed to characterize the relationship between EDA and auditory stimulus intensities. Acoustic stimulus used in this study were 500 Hz, 1 kHz, 2 kHz of narrow band noise, which were representative of speech frequencies in audible range. Stimulus intensity between 90 and 30 dB in 10 dB within dynamic range. After deriving the minimum stimulus intensity(threshold of skin potential) which elicited skin potential, and then the latency and amplitude were derived from waveform of skin potential, each latency and amplitude were compared to stimulus intensity. The waveform of skin potential were recorded stably, and the threshold of skin potential appeared nearly the hearing threshold level of the participant. The latency was decreased and the amplitude was increased according to the increase of the stimulus intensity. These results suggest that auditory evoked skin potential can be applicable to auditory assessment and audiological diagnosis tool.

• 수산해양기술연구
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• 제35권4호
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• pp.391-396
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• 1999

It is well known that fish hear a wide frequency range of sound using both laterial line and inner ear, and the sound is probably the most effective channel for long-range communication underwater than any other stimulus.The auditory threshold of svenband grouper, Epinephelus septem fasciatus was determined by conditioning method using a sound coupled with electric shock in a tank. The audio-signals and electric shock used in the experiment were pure tones of 100 to 1000Hz and DC 6n.The response of fish to the sound was observed by ECG intervals from precordial leads method (V1·V2 method). The auditory threshold curve for sevenband grouper was V-shaped, with most sensitive threshold at 350Hz in the range of 100~1000Hz. The Sevenband grouper were more sensitive to sounds of 200~400Hz than to adjacent frequencies.

• 수산해양기술연구
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• 제35권2호
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• pp.156-160
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• 1999

제주 연안역에 있어서 해양목장의 음향순치 대상 어종으로 선정할 수 있는 연안 정착성 어류인 쏨뱅이의 청각 능력을 파악할 목적으로, 임의의 순음과 전기자극을 이용하여 육상수조에서 조건 학습시킨 후, 주파수와 음압을 임의로 변화시켜가면서 쏨뱅이의 심전도를 도출하여 심박간격의 변화로부터 청각 문턱치 곡선을 구한 결과, 쏨뱅이는 실험에서 사용한 측정 주파수 80Hz～800Hz의 순음을 인식하고 있었다. 각 주파수에 대한 청각감도는 주파수 80Hz～200Hz에서는 민감하게 나타났으나, 주파수 500Hz 이상에서는 감도가 급격히 나빠지고 있었다. 청각 문턱치는 주파수 100Hz에서 약 90㏈ 의 음압으로 최소였으며, 주파수 300Hz 이상에서 급격하게 상승하는 경향을 보이면서 주파수 500Hz에서 약 127㏈의 음압으로 최고치를 나타내었다.

• 한국수산과학회지
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• 제33권6호
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• pp.581-584
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• 2000

제주 연안역에 서식하고 있는 볼락의 수중음에 대한 청각 특성을 파악하여 수중음에 대한 어군의 행동양상을 파악할 수 있는 기초자료를 제공할 목적으로 측정주파수 $80{\~}800 Hz$의 수중음과 8V의 직류 전압의 전기자극을 이용하여 음향 조건학습을 시킨 후 측정주파수와 음압을 임의로 변화시켜가면서 청각문턱치를 구한 결과 볼락은 측정주파수 $80{\~}800 Hz$의 음을 인식하고 있었고, 측정주파수에 대한 각각의 청각문턱치는 102 dB, 103 dB, 99 dB, 96 dB, l16 dB, 122 dB이었으며, 측정 주파수 300 Hz에서 음압 96 dB로 가장 낮고 측정 주파수 800Hz에서 음압 122 dB로 가장 높게 나타내고 있었다. 그러나 수중에 존재하는 소음의 주파수대역이 저주파에서 높게 나타나고 대역폭도 넓으므로 이들 자극이 어류 행동에 어떻게 미치고 있는지 규명할 필요가 있다고 판단된다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1991년도 춘계학술대회
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• pp.43-46
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• 1991

In this study, peripheral auditory system has been modeled as a filter bank of overlaping bandpass filters, and auditory filter shape has been estimated by notch noise masking. The filter was centered at 1kHz, and noise level was set to 40dB SPL. Masker noise was generated by summing sinusoidal functions with random phase for very steep skirts. To estimate threshold we used two alternative forced choice with 500 msec of duration. We measured threshold with notch width at 0.05,0.1,0.2,0.3,0.4 and 0.5. The filter was asymmetric with steeper upper branch and its ERB was 168 - 192 Hz.

• 한국수산과학회지
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• 제35권6호
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• pp.563-567
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• 2002

Developing base data on luring fish schools into netting position by the use of underwater audible sound on japanese parrot fish Oplegnathus fasciatus found in the coastal waters of Jeju Island, S. Korea. Auditory threshold was determined by the heartbeat condition technique using pure tones coupled with a delayed electric shock. The audible range of japanese parrot fish extended from 80 Hz to 500 Hz with a peak sensitivity at 200 Hz. The mean auditory thresholds at the frequencies of 80 Hz, 100 Hz, 200 Hz,300 Hz and 500 Hz were 104 dB, 95 dB, 91 dB, 99 dB and 113 dB, respectively. As the frequency became higher than 200 Hz, the auditory threshold increased almost linearly with increasing frequency. Critical ratios of fishes measured in the presence of masking noise in the spectrum level range of 69$\~$78 dB (0 dB re 1$\mu$Pa/$\sqrt{Hz}$) ranged from 21 dB to 40 dB at test frequencies. The noise spectrum level at the start of masking was about 70 dB within the test frequency range. The sound pressure level of 100$\~$200 Hz recognized by japanese parrot fish under the ambient noise is above 91 dB and the critical ratio for them is above 21 dB.

• 한국임상수의학회지
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• 제15권2호
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• pp.410-416
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• 1998

These experiments were designed to evaluate the possibility of brain-stem auditory evoked responses(BAER) as a diagnostic tool for deafness in dogs. The BAER was recorded from three different groups of dogs; the normal dogs,'dog with otitis externa and dogs with unilateral destruction of cochlear. BAER of the normal dogs was consisted of distinct five peaks(I, II, III-IV, V). Furthermore, the clear shapes of waveform were observed at 85 dB. The latency of BAER was increased with reducing the intensity of sound-stimulus. The highest threshold of BAER was measured at 2 KHz with 10-30 dB. Dog with otitis externs demonstrated unclear shapes of BAER compared to the that of normal dogs. In the dogs with unilateral destruction of cochlear, the flat and indistinct waveform of BAER was recorded from the cochlear destroyed ear while that of BAER from normal side of ears did not show any differences from the normal BAER. These results indicate that the BAER can be clinically used in order to diagnose the deafness in dogs.