• 한국소음진동공학회논문집
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• 제19권9호
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• pp.928-934
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• 2009

Underwater impulsive sound such as underwater blasting noise, piling noise and stone breaking hammer affects marine animal hearing response and organs. This study describes the characteristics of various impulsive noise from waterfront construction site and their effect on fish. Time constant, peak pressure, energy and SEL(sound exposure level) of four different underwater impulsive sounds are quantified. Auditory and non-auditory tissue damage ranges are derived by comparing their quantities to the exposure criteria for fish. Damage ranges of auditory tissue and non-auditory tissue of underwater boring blast of 150 kg of charge, are about 100 m and 300 m, respectively. Other three impulsive sounds also gives damage effects but less than that of underwater boring blast.

• International Journal of Molecular Medicine
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• 제44권4호
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• pp.1473-1483
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• 2019

One of the primary theories of the pathogenesis of tinnitus involves maladaptive auditory-somatosensory plasticity in the dorsal cochlear nucleus (DCN), which is assumed to be due to axonal sprouting. Although a disrupted balance between auditory and somatosensory inputs may occur following hearing damage and may induce tinnitus, examination of this phenomenon employed a model of hearing damage that does not account for the causal relationship between these changes and tinnitus. The present study aimed to investigate changes in auditory-somatosensory innervation and the role that axonal sprouting serves in this process by comparing results between animals with and without tinnitus. Rats were exposed to a noise-inducing temporary threshold shift and were subsequently divided into tinnitus and non-tinnitus groups based on the results of gap prepulse inhibition of the acoustic startle reflex. DCNs were collected from rats divided into three sub-groups according to the number of weeks (1, 2 or 3) following noise exposure, and the protein levels of vesicular glutamate transporter 1 (VGLUT1), which is associated with auditory input to the DCN, and VGLUT2, which is in turn primarily associated with somatosensory inputs, were assessed. In addition, factors related to axonal sprouting, including growth-associated protein 43 (GAP43), postsynaptic density protein 95, synaptophysin, α-thalassemia/mental retardation syndrome X-linked homolog (ATRX), growth differentiation factor 10 (GDF10), and leucine-rich repeat and immunoglobulin domain-containing 1, were measured by western blot analyses. Compared to the non-tinnitus group, the tinnitus group exhibited a significant decrease in VGLUT1 at 1 week and a significant increase in VGLUT2 at 3 weeks post-exposure. In addition, rats in the tinnitus group exhibited significant increases in GAP43 and GDF10 protein expression levels in their DCN at 3 weeks following noise exposure. Results from the present study provided further evidence that changes in the neural input distribution to the DCN may cause tinnitus and that axonal sprouting underlies these alterations.

• 감성과학
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• 제2권2호
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• pp.37-42
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• 1999

Long-term exposure to loud noise affects performance since it changes arousal level, distracts attention, and also is able to evoke subjective stress accompanied by negative emotional states. The purpose of the study was to analyze dynamics of subjective and physiological variables during a relatively long-lasting (30 min) exposure to white noise (85 dB[A]). Physiological signals were recorded on 15 college students during 30 min of intense auditory stimulation. Autonomic variables, namely skin conductance level , non-specific SCR number, inter-best intervals in ECG, heart rate variability index (HF/LF ratio of HRV), skin temperature, as well as respiration rate were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated every 5 min. Statistical analysis was employed to trace the time course of the dynamics of subjective and autonomic physiological variables and their relationships. Results showed that the intense noise evoked subjective stress as well as associated autonomic nervous system responses. However it was shown that physiological variables endured specific changes in the process of exposure to the loud white noise. Discussed were probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity, namely short-term activation, followed by transient adaptation (with relatively stable autonomic balance) and then a subsequent wave of arousal due to tonic sympathetic dominance.

• Journal of Ginseng Research
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• 제34권4호
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• pp.336-341
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• 2010

One mechanism of inner ear damage by noise-induced hearing loss (NIHL) is the production of reactive oxygen species (ROS). Because Korean red ginseng (KRG) has an anti-ROS effect in various tissues, KRG may have a role in preventing NIHL. A window period exists in which ROS formations continue after noise exposure, and further damage can be prevented by antioxidants. In this study, we aimed to investigate the effects of KRG after exposure to noise. KRG (200 mg/kg) was fed to mice for 3 days after noise exposure. The change in hearing level was analyzed by measuring the auditory brainstem response. To induce a temporary threshold shift (TTS) of hearing, mice were exposed to 110 dB white noise for 3 hours. Fast recovery of hearing was observed in mice fed KRG 1 hour and 1 day after noise exposure for 3 days. The expression of 8-oxoguanine was not observed in the inner ears of mice fed KRG 1 hour after noise exposure, but was evident in the stria vascularis of mice in the control group (noise exposure only). From this study, we conclude that KRG acted as an effective inhibitor of NIHL in TTS cases.

• 대한청각학회지
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• 제23권3호
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• pp.160-166
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• 2019

Lots of neuroimaging and animal studies have revealed that tinnitus and hyperacusis share the same patterns in the bottom up central auditory process. The aim was to identify the abnormal central patterns commonly observed in both tinnitus and hyperacusis in humans. We investigated two cases of normal hearing: a tinnitus patient and a hyperacusis patient. We compared the differences between the severe temporal hyper-activated state (STHS), with spikes, fast beta and gamma frequencies after noise exposure, and the mild temporal hyperactivated state (MTHS), in no sound exposed condition. The power of the gamma band in the two cases was increased in both auditory cortices compared to the other brain regions. Our results of human with normal hearing were the first to identify how tinnitus and hyperacusis caused by sound are abnormally active and how they maintain constant pathological states.

• Journal of Audiology & Otology
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• 제23권3호
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• pp.160-166
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• 2019

Lots of neuroimaging and animal studies have revealed that tinnitus and hyperacusis share the same patterns in the bottom up central auditory process. The aim was to identify the abnormal central patterns commonly observed in both tinnitus and hyperacusis in humans. We investigated two cases of normal hearing: a tinnitus patient and a hyperacusis patient. We compared the differences between the severe temporal hyper-activated state (STHS), with spikes, fast beta and gamma frequencies after noise exposure, and the mild temporal hyperactivated state (MTHS), in no sound exposed condition. The power of the gamma band in the two cases was increased in both auditory cortices compared to the other brain regions. Our results of human with normal hearing were the first to identify how tinnitus and hyperacusis caused by sound are abnormally active and how they maintain constant pathological states.

• 한국음향학회지
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• 제29권3호
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• pp.184-190
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• 2010

최근 노화현상 외에도 소음으로 인한 청력저하를 호소하는 사례가 늘어나고 있다. 특히 멀티미디어의 보급과 휴대용 정보기기의 발달로 지속적인 소음에 장시간 노출되어 청각 세포의 손상이 발생하여 청력 손실이 발생하는 소음성 난청 인구가 증가하고 있는 실정이다. 현재 병원에서 실시하고 있는 순음청력검사는 8000 Hz까지의 주파수대역을 수동으로 조절하며 검사하므로 8,000 Hz 이상의 확장 고주파수에서도 손실을 가져오는 소음성 난청의 경우 회화 영역에 직접적인 영향을 미치지 않아 조기에 청력저하를 파악하여 예방하기에는 부적합한 단점이 있다. 본 논문에서는 12,000 Hz∼20,000 Hz 고주파 대역을 이용하여 소음성 난청을 조기에 파악하여 예방하기 위한 청력측정법을 제안하였다. 휴대용 정보기기를 통해 이어폰을 많이 사용하는20대 남녀 50명을 대상으로 제안한 측정법으로 청력을 측정한 결과 36 %가 소음으로 인한 청력 저하를 보였다. 그 중 2 %는 청력의 손실정도가 심각함을 보였다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1999년도 추계학술대회 논문집
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• pp.211-215
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• 1999

It is well known that a long-term exposure to a loud noise environment affects performance, since it distracts attention, and also is able to evoke stress accompanied by negative emotional states. The purpose of this study was to analyze dynamics of subjective and physiological variables during long-lasting (30 min) exposure to intensive white noise (85 dB[A]). Physiological signals on 23 college students were recorded by BIOPAC, Grass Neurodata systems and AcqKnowledge 3.5 software. Autonomic variables, namely skin conductance level (SCL), non-specific SCR number (N-SCR), inter-beat intervals in ECG (RR intervals), heart rate variability index (HF/LF ratio of HRV), respiration rate (RESP), and skin temperature (SKT) were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated on every 5 min basis. Regression and correlation analyses were employed to trace the time course of the dynamics of the subjective and autonomic physiological variables and their relationship. Results showed that intense noise evokes subjective stress with associated autonomic nervous system responses. However, it was shown that physiological variables endure specific changes in the process of exposure to loud white noise. Discussed are probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity.

• 한국소음진동공학회논문집
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• 제26권6_spc호
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• pp.674-679
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• 2016

According to the conventional studies on the noise and cardiovascular effect, railway noise is better associated with hypertension and adverse cardiovascular events than road traffic noise. But the underlying mechanisms remain unclear. We investigated the hypothesis that exposure to acute railway noise would the unfavorable effect of cardiovascular and autonomic system in healthy young subjects. Using a randomized, sham-controlled cross-over design, ten subjects were assigned to receive either an exposure to high speed train noise (84 dB) for 30 minutes or a control condition (non noise), separated by two days. Blood pressure, heart rate, augmentation index and heart rate variability as indices of cardiovascular and autonomic system function were measured at baseline, during, and recovery from two trials. The results show that exposure to acute railway noise significantly increased diastolic blood pressure and augmentation index, which may cause of adverse cardiovascular effects.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 춘계학술발표회
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• pp.207-212
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• 2006

선박에서 선내 소음이 문제로 인식되기 시작한 시기는 1970년대 초반 유럽에서 선박소음규제를 명문화하기 시작한 때로서 이 후 1982년 국제해사기구 (IMO) 에서 "International Code on Noise Levels on Board Ships"가 채택되어 오늘날에는 거의 모든 신조 선박에 대하여 해당하는 조항의 적용이 명문화되었다. 특히, 대형의 디젤기관과 다수의 보조기계가 통시에 운전되어지는 기관실 내부는 크고 복잡한 소음이 발생하는 환경으로 되어지고, 이러한 환경에서 작업하는 작업자는 소음성난청으로 되기 쉽다. 최근에는 각 나라별로 직업상의 난청으로부터 작업자를 보호할 목적으로 허용소음 폭로 시간을 법적으로 규제하고 있다. 우리나라에서는 근로기준법에서 정의하고 있지만 선박의 기관실과 같이 특수한 조건에 대해서 국제해사기구의 규정에 따르고 있다. 본 논문에서는 국내 서남 연안을 정 기적으로 운항하고 있는 저속의 화객선에 대한 소음의 정도를 조사하였다.