• Proceedings of the KOR-BRONCHOESO Conference
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• 1977.06a
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• pp.4.1-4
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• 1977

A variety of diagnostic means for evaluating the hearing ability of neonates and infants have been studied so far, and some physical responses of neonates and infants to loud sound is still of much value. The author studied some normal responses of 100 neonates (male 54, female 46) in our neonatal room from Jan, 1977 to April, 1977. We took 90dB pure tone at 3, 000Hz by Beltone Audiometer model l0D (ANSI 1969) for a stimulus. The results are as follows: 1. The range of the examinees' age is between 2 and 3.5 hours (average 2.4 hours), and auropalpebral response is in 39% (eyelid blinking 10%, eyelid widening 29%), Moro reflex in 35%, sucking response in 14%, cessation of movement in 6%, head turning response in 2%, and no response in 4%. 2. The duration of response is between 2 and 5 Seconds (average 3.3 seconds).

• Journal of IKEEE
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• v.16 no.4
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• pp.395-404
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• 2012

In this paper, the perceived loudness metering algorithm based on ITU-R BS.1387-1 was investigated and implemented, and its performance was evaluated by applying to 23 pure tones and 9 digital audio samples. Error of the tone test results compared with ISO226:2003 was below 5%, and sample test results, in comparison with Moore's algorithm, showed deviation of less than 4.7% and correlation of 0.96. On the other hand, it was investigated how the implemented algorithm's performance was subject to auditory pitch scale. Its result showed that the algorithm with 37 auditory filters, through correcting a bias effect, has a good performance of less than 2% in comparison with the one with 109 auditory filters.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.7
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• pp.1069-1076
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• 2012

We use largely two methods, how to control the noise of the KTX, they are the passive noise control method and the active noise control method. The passive noise control has been used in a variety of ways since the KTX opening day, but lately it has shown the technical limitations by being dropped sharply. So, it is getting important to conduct the research about ANC that is able to reduce the ambient noise when the environmental-factor changes and be installed easily. To reduce a three-dimensional closed-space sound field like a car of a high-speed rail is hard to do using single channel ANC control system. Therefore we have to model the paths of the noise exactly for reducing the noise. And the control speakers and the error mics should be designed for optimal position. In this paper, we designed the transfer functions for modeling the noise paths under the influence of the distance between control speakers & error mics and primary noise speaker in TEST-BED where there is modeled as actual interior of KTX. We have made the modeling and the simulations of interior environment of KTX car by using three frequency bands of 120Hz, 280Hz, 360Hz. After the modeling, we compared the performance of active noise control and also we analyzed what to affect with difference in distance. After comparing of the performance using Pure Tone 120Hz, 280Hz, 360Hz at each modeling and then we simulated ANC for KTX's interior noise which we measured really and analyzed.

• Journal of Clinical Otolaryngology Head and Neck Surgery
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• v.29 no.2
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• pp.235-239
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• 2018

Due to the structure with one end closed, the external ear resonance effect in which the high frequency is amplified can be generated, and the sound can be perceived well. The external ear resonance normally has a first peak and a second peak. On average, the first peak has a gain of 18.6 dB at 2620 Hz and the second peak has a gain of 18.2 dB at 4210 Hz. The resonance of the external auditory canal changes with the state of the tympanic membrane, the presence of the ventilation tube, and the structure (length, diameter, shape) of the external auditory canal. A patient with a postauricular meatomastoid cutaneous fistula was admitted to the hospital with a foreign body which is the molding of the hearing aid. After removal of the foreign body, the resonance of the external auditory canal was lost and the subjective sound cognitive ability decreased. In the case of postauricular meatomastoid cutaneous fistula, we confirmed the improvement of sound cognitive ability, the change of pure tone hearing threshold, and the change of the external ear resonance after reconstruction of the ear canal without middle ear reconstruction.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.32 no.3
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• pp.212-223
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• 2019

Objectives : The purpose of this study is to report three cases of Korean medical treatment for sudden sensorineural hearing loss(SSHL). Methods : This study conducted with three sensorineural hearing loss patients who hospitalized in Ophthalmology, Otolaryngology & Dermatology Clinic of Korean Medical Hospital. Three patients were treated with herbal medicine(Sunkihwalhyeol-tang, Ikgibohyeol-tang, Gongjindan) and acupuncture. After treatment, we evaluated Siegel's Criteria with pure tone audiometry and subjective symptoms alteration. Results : All three patients were completely recovery about Siegel's Criteria and improved subjective symptoms after treatment. Conclusions : This study suggests that Korean medical treatment may be effective about SSHL.

• Korean Journal of Community Nutrition
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• v.25 no.6
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• pp.512-519
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• 2020

Objectives: A cross-sectional study was conducted to investigate the associations between food groups and hearing loss. Methods: Data of 1,312 individuals were used from the Korea National Health and Nutrition Examination Survey 2013. Hearing loss was determined with a pure tone average (PTA) of greater than 25 dB in either ear. The PTA was measured as the average hearing threshold at speech frequencies of 0.5, 1, 2, and 4 kHz. The dietary intake was examined with a food frequency questionnaire with 112 food items. The food items were classified into 25 food groups. A weighted logistic regression was used to investigate the association. Results: Individuals in the highest tertile of vegetables and nuts food groups were less likely to have hearing loss than those in the lowest tertile [Odds Ratio (OR) = 0.58 (95% Confidence interval (CI) 0.38-0.91), P = 0.019; OR = 0.59 (95% CI 0.39-0.90), P = 0.020, respectively], after adjusting for confounding variables of age, sex, body mass index, drinking, smoking, diabetes, hypertension, and physical activity. Conclusions: In this cross-sectional study, we observed that high intake of vegetables and nuts food groups revealed significant inverse associations with hearing loss, after adjusting for confounding variables among 1,312 participants.

• Journal of Audiology & Otology
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• v.25 no.3
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• pp.146-151
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• 2021

Background and Objectives: The relationship between hearing aid (HA) use and improvement in cognitive function is not fully known. This study aimed to determine whether HAs could recover temporal resolution or hearing in noise functions. Materials and Methods: We designed a prospective study with two groups: HA users and controls. Patients older than 45 years, with a pure tone average threshold of worse than 40 dB and a speech discrimination score better than 60% in both ears were eligible. Central auditory processing tests and hearing in noise tests (HINTs) were evaluated at the beginning of the study and 1, 3, 6, and 12 months after the use of a monaural HA in the HA group compared to the control group. The changes in the evaluation parameters were statistically analyzed using the linear mixed model. Results: A total of 26 participants (13 in the HA and 13 in the control group) were included in this study. The frequency (p<0.01) and duration test (p=0.02) scores showed significant improvements in the HA group after 1 year, while the HINT scores showed no significant change. Conclusions: After using an HA for one year, patients performed better on temporal resolution tests. No improvement was documented with regard to hearing in noise.

• Journal of Audiology & Otology
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• v.25 no.2
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• pp.65-71
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• 2021

Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.

• The Journal of the Acoustical Society of Korea
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• v.41 no.1
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• pp.45-51
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• 2022

Sound quality evaluation is one of the psychoacoustic methods to measure subjective judgements for sound color. The purpose of this study is to investigate sound quality benefits of bimodal users by comparing sound quality scores between bimodal hearing condition and unilateral cochlear implant(CI) condition as a preliminary study. Thirteen bimodal users and seven unilateral CI users were participated in this study. Audiologists performed pure tone and speech audiometry and measured functional gain and real-ear insertion gain. Subjective assessment of sound quality was followed with four sounds including violin sound, male and female voices, and refrigerator noise. Participants judged the sound quality with six sound quality index. Bimodal users showed mean 0.8 points more sound quality improvements in bimodal condition than unilateral CI condition. Group comparison between bimodal and unilateral CI users showed no differences. A follow-up study of sound quality tools and methods should be considered to evaluate subjective bimodal benefits of cochlear implant users.

• Korean Journal of Audiology
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• v.24 no.1
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• pp.24-28
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• 2020

Background and Objectives: Systemic steroid therapy (SST) and intratympanic steroid injection (ISI) have been the treatment of choice for sudden sensorineural hearing loss (SSNHL). We studied the effect of ISI administered at different intervals on hearing outcomes in patients with SSNHL. Subjects and Methods: We performed a retrospective study of 427 patients diagnosed with SSNHL at Bundang Jesaeng Hospital, of whom 51 patients with SSNHL who received SST and four ISIs were included in this study. Patients were treated with four ISIs either every day for 4 days (group 1) or at intervals (mean duration of interval: 2.21 days) (group 2). Hearing outcomes were evaluated using the pure-tone test before the injection and 14 days, 1 month, and 3 months after the final injection. Recovery rates were classified based on Siegel's criteria. Results: The amount of improvement was 27.67 dB (±20.45) in group 1 and 32.79 dB (±21.42) in group 2. However, there were no significant differences between the two groups (p= 0.714). The recovery rates based on Siegel's criteria were 18/27 (66.7%) and 16/24 (66.7%) in groups 1 and 2, respectively, with no significant difference (p=1.000). Considering only complete recoveries in hearing recovery, the recovery rates were 15/27 (55.6%) and 14/24 (58.3%) in groups 1 and 2, respectively, with no significant difference (p=0.842). Conclusions: There were no significant differences in hearing outcomes or recovery rates after ISI administration every day or at intervals of 2-3 days.