Junghak Lee

Development of Korean Standard Sentence Lists for Sentence Recognition Tests

유소아기 청력손실은 언어습득 및 언어발달, 학습 및 정서심리 등에 지대한 영향을 미치므로 가능한 조기에 발견하고 중재해야 한다. 이러한 일련의 과정에서 어음청각검사를 통하여 어음인지능력을 적절히 평가하고 이를 바탕으로 중재를 도모하는 일은 무엇보다 중요하다. 어음인지도(speech recognition score)는 듣기에 가장 적절한 강도로 어음을 제시하였을 때 정확히 확인하는 정도(%)를 측정하는 것28)으로 일상생활의 듣기능력에 대한 정보 제공뿐만 아니라 청력손실 병변 부위, 보장구의 선택 및 적합, 재활의 평

Phoneme-Based Self Hearing Assessment on a Smartphone

Phonemes provide an interesting alternative to pure tones in hearing tests. We propose a new smartphone-based method for self-hearing assessment using the four Korean phonemes which are similar to the English phonemes /a/, /i/, /sh/, and /s/. We conducted tests on 15 subjects diagnosed with mild to severe hearing loss and estimated their conventional pure-tone hearing thresholds from their phoneme hearing thresholds using regression analysis. The phoneme-based self-hearing assessment was found to be sufficiently reliable in estimating the hearing thresholds of hearing-impaired subjects. The difference between the hearing thresholds obtained through conventional pure-tone audiometry and those obtained using our method was 5.6 dB HL on average. The proposed hearing assessment was able to significantly reduce the mean test time compared to conventional pure-tone audiometry.

Development of Korean Standard Monosyllabic Word Lists for Adults (KS-MWL-A)

Development of Korean Standard Monosyllabic Word Lists for Adults (KS-MWL-A) Jin-Sook Kim, Dukhwan Lim, Ha-Na Hong, Hyun-Wook Shin, Ki-Do Lee, Bin-Na Hong and Jung-Hak Lee Department of Speech Pathology & Audiology, College of Natural Sciences, Hallym University, Chuncheon, Korea Graduate Program in Audiology, Hallym University, Chuncheon, Korea Department of Speech Pathology & Audiology, Nambu University, Gwangju, Korea Department of Audiology, Hallym Institute of Advanced International Studies, Seoul, Korea Word recognition test (WRT) presented at the most comfortable loudness level can provide valuable informations for diagnosing the degree of communication disability, prescribing hearing instruments, planning aural rehabilitation and speech therapy, and determination of site of lesions. The purpose of this study was to develop the Korean standard monosyllabic word lists for adults (KS-MWL-A). Considering the criteria given by the literatures such as phonetic balance, equal range of phonetic composition of speech, words in common usage, and words’ familiarity, etc, first 1,456 candidating monosyllabic words were selected. Those were extracted from the conventional lists, the first and second graded familiar words, and the words that were included in the dictionary. In order to reflect the actual frequencies of syllable in colloquialism, initial and final consonants’ and vowels’ frequencies in everyday dialogue were investigated and controlled. The KS-MWL-A was developed with selected final 200 monosyllabic words, followed by examinations of psychometric functions and homogeneity of the stimulus twice and corrections referred by the experts. The first and the second psychometric function tests were performed to 30 young adults (mean age:22) and to 48 young adults (mean age:21.5), respectively at 12 steps of intensity from -10 to 45 dBHL in 5 dBHL steps and psychometric function curves were obtained using the logistic regression equation. The mean slope was 8.81 and the words that were within 1.50 and 1.96 standard deviations of the slope and the level were only included. The KS-MWL-A 200 words were composed of conventional word lists by Hahm (1962) with 53.5% (107 words) and the first and second graded familiarity words with 93.5% (187 words). Also, consonant-vowel-consonant formation and noun class were mostly composed with 52% (104 words) and 97.5% (196 words). Four lists were balanced based on equal average difficulty and equal phonetic composition and homogeneity. List 1, 2, 3, 4’s slope means were analyzed by one way ANOVA according to the type of the list-full list with 50 words, half list with 25 words, and quick list with 10 wordsand showed 0.37, 0.32, and 0.09 probability value. This indicates there should be no clinical difference among four lists used with the type of lists. And the type of the lists’ slope means were analyzed by one way ANOVA according to the four different 1, 2, 3, and 4 lists and showed 0.91, 0.62, 0.57 and 0.09 probability value. This indicates there should be no clinical difference among type of the list used with the different four lists as well. However, there were some limitations in developing the KS-MWL-A for that graded familiarity was not systematical, that psychometric functions should have been analyzed for all the drafted lists, that the frequency of the final consonant was analyzed tentatively, and that the word frequency and lexical effects were not considered based on the neighborhood activation model. Further verification of this study should be performed for better Korean monosyllabic word lists.

Hearing Thresholds for a Geriatric Population Composed of Korean Males and Females.

Background and Objectives The purpose of the present study was to provide the hearing threshold levels in the elderly Korean population, and to compare Korean data with that in the International Organization for Standardization (ISO) 7029 (2000). Subjects and Methods Data were collected from a total of 526 ears from 112 males and 151 females aged 60-84 years. All participants were screened otologically by the procedure given in ISO 8253-1 (2010). Results Results showed that the pure-tone average was gradually elevated with increasing age. The amount of hearing loss was greater in males than in females, and the high frequency hearing thresholds were worse than the low frequency hearing thresholds in males and females. The hearing threshold levels were higher at low frequencies in males and at all frequencies in females than the norms of ISO 7029 (2000). Conclusions Results from this study will be partly used for standardization of hearing thresholds as a function of age in Korea and for updating the ISO 7029.

The Maximum Permissible Ambient Noise and Frequency-specific Averaging Time on the Measurement of Distortion Product Otoacoustic Emissions

The effects of ambient noise and averaging time on distortion product otoacoustic emission (DPOAE) measurements were systematically examined in 20 normally hearing adults. For each frequency from 0.7 to 6 kHz, 2f1-f2 DPOAEs were measured at nine intensity levels of ambient noise for each of four different averaging times. The dependent variable of interest was the DPOAE:noise ratio (D:N)--the relationship between DPOAE amplitude and noise level at 2f1-f2. Findings indicated that, relative to the baseline condition (25 dBA), ambient noise levels of 40 dBA or greater affected the D:N considerably in the lower frequencies. However, noise levels of 55-65 dBA did not affect the D:N in the higher frequencies. Results also indicated that, to achieve detectable DPOAEs, longer averaging times were required as ambient noise increased and as frequency decreased. Based on the results, the maximum permissible ambient noise levels (MPANLs) were estimated in relation to averaging time.

Test-Retest Reliability of Word Recognition Score Using Korean Standard Monosyllabic Word Lists for Adults as a Function of the Number of Test Words.

Background and Objectives The purpose was to establish the test-retest reliability of word recognition score (WRS) using Korean standard monosyllabic word lists for adults (KS-MWL-A) recently developed based on the international standard for speech audiometry (ISO 8253-3:2012). Subjects and Methods Subjects consisted of 159 adults aged to 18 to 25 years with normal hearing sensitivity. WRSs were obtained in 2 dB steps from the level of speech recognition thresholds to the level of 86% correct responses or greater. After one or two weeks, retest was performed. Correlation, confidence interval (CI) and prediction interval (PI) were calculated for the reliability. Results Correlation coefficients were 0.88 for 50 test words, 0.76 for 25 and 0.61 for 10 words. Results also showed that 95% CIs and PIs were narrower for 25 and 50 test words than those for 10 test words. Conclusions Korean WRS using the KS-MWL-A has high reliability for 25 and 50 test words, but relatively low for 10 words. It suggested that 95% CIs for each test words would be criteria for significant differences in WRS for groups and 95% PIs at each score of WRS could be utilized for a considerable difference for each individual at retest.

Study on self hearing assessment using speech sounds

In this study, we proposed new self assessment of hearing loss in mobile phones and realized a function of compensation for hearing impaired person. The results of experiments on mobile phone showed that the proposed hearing test is sufficient to check hearing loss and the compensation based on the result of the proposed hearing test can improve speech intelligibility of hearing impaired persons.

Reference sound pressure level for Korean speech audiometry

Abstract Objective: The purpose of this study was to examine the reference sound pressure level (RSPL) for Korean speech audiometry which was defined as the reference speech recognition threshold level (RSRTL) equivalent to 0 dB HL at the audiometer. Study sample: Subjects consisted of 20 adults (40 ears) with normal hearing sensitivity. Design: Puretone thresholds (PTs) were obtained in 2 dB steps at each octave band. The newly developed Korean bisyllabic words were used to establish the speech recognition thresholds (SRTs). The SRT was the level at 50% correct responses based on the psychometric function performed from -8 dB HL (12 dB SPL) up to the level at or above 90% correct responses in 2 dB steps. Results Conclusions: The mean SRT was 23.44 dB SPL for sets comprised of 36 Korean bisyllabic words. Thus, the difference between English and Korean RSRTLs was about 3.44 dB. We recommend further study to recalculate the RSRTL for Korean speech audiometry with more subjects. Sumario Objetivo: El propósito de este estudio fue examinar el nivel de presión sonora de referencia (RSPL) para la logoaudiometría en coreano, que fue definido como el nivel umbral de referencia para el reconocimiento del lenguaje (RSRTL), equivalente a 0 dB HL en el audiómetro. Muestra Del Estudio: Los sujetos de estudio fueron 20 adultos (40 oídos) con sensibilidad auditiva normal. Diseño: Se obtuvieron umbrales tonales puros (PT) en pasos de 2 dB para cada banda de octava. Se usaron las recientemente desarrolladas palabras bisilábicas coreanas para establecer los umbrales de reconocimiento del lenguaje (SRT). El SRT fue el nivel donde se obtuvo un 50% de respuestas correctas, con base en la función psicométrica realizada desde −8 dB HL (12 dB SPL) hasta un nivel ubicado donde se logra un 90% o mayor de respuestas correctas, en pasos de 2 dB. Resultados Y Conclusiones: La mediana del SRT fue de 23.44 dB SPL para listas de 36 palabras bisilábicas coreanas. Por tanto, la diferencia entre el SRT en coreano y en inglés fue de 3.44 dB. Recomendamos estudios adicionales para recalcular el RSRTL para la logoaudiometría en coreano con más sujetos.

Development of School Aged and Preschool Korean Bisyllabic Word Lists for Speech Recognition Threshold Test

SooJin Cho, JungHak Lee, Dukhwan Lim, KyungWon Lee and HeeKyung Han Department of Speech Pathology & Audiology, Daebul University, Yeongam, Korea Department of Audiology, Hallym Institute of Advanced International Studies, Seoul, Korea Division of Audiology and Speech Pathology, Hallym University, Chuncheon, Korea Inter-Disciplinary Program of Speech Pathology & Audiology, Graduate School, Hallym University, Chuncheon, Korea

Development of Web-Based Platform for Auditory Rehabilitation

세계는 제4차 산업혁명의 시대로 진입하였으며 정보의 처리 능력, 저장 용량 및 접근성이 기하급수적으로 발전하여 삶의 질을 향상시킬 다양한 기술과 서비스가 빠르게 증가하고 있다 (Schwab, 2017). 헬스케어 분야에서 유전학, 로봇 공학, 나노 기 술, 3D 프린팅 및 생명공학의 발전은 진단의 정확성과 치료의 효율성을 높였으며, 인공지능과 클라우드 기반의 컴퓨터 시스템 은 지속적인 모니터링과 통합적인 재활 서비스를 가능하게 하였 다(Saniee et al., 2017). 정보통신기술은 이 혁명의 중추라 할 수 있으며 광대역 인터넷은 세계에서 가장 중요한 범용 기술 중 하 나로써 수십억 명의 사람들과 그 주변의 사물들을 웹에 연결하 여 사회와 경제 전반에 영향을 주는 변화를 이끌고 있다. 청각학 분야에서는 다양한 디지털 콘텐츠와 인터넷을 통한 서비스가 개발되고 있으며 전통적인 방식과 비교하여 신뢰성과 효과가 입증되고 있다(Swanepoel & Hall, 2010). 기존의 연구 를 살펴보면 청각선별검사(Bexelius et al., 2008; Smits et al., 2006), 진단(Choi et al., 2007; Yao et al., 2010), 적합(Ferrari et al., 2009; Ramos et al., 2009), 훈련(Lee, 2017; Sweetow & Sabes, 2006; Yu et al., 2014), 상담(Laplante-Lévesque et al., 2006) 등 청각재활의 많은 분야에서 온라인 서비스로의 전환 이 이루어지고 있다. 컴퓨터와 인터넷을 이용한 청각재활은 시 간과 비용 측면에서 비용효율적이고, 많은 사람이 적기에 쉽게 진단을 받고 적절한 개입과 중재를 받을 수 있도록 접근성을 높 Development of Web-Based Platform for Auditory Rehabilitation Wonjin Lee, Junghak Lee Audiol Lab, Seoul, Korea Department of Audiology, Hallym University of Graduate Studies, Seoul, Korea