Speech Perception and Gap Detection Performance of Single-Sided Deafness under Noisy Conditions

곽찬범,김세아,이지현,서영준,공태훈,한우재 대한청각학회 2019 Journal of Audiology & Otology Vol.23 No.4

Background and Objectives: Many studies have reported no benefit of sound localization, but improved speech understanding in noise after treating patients with single-sided deafness (SSD). Furthermore, their performances provided a large individual difference. The present study aimed to measure the ability of speech perception and gap detection in noise for the SSD patients to better understand their hearing nature. Subjects and Methods: Nine SSD patients with different onset and period of hearing deprivation and 20 young adults with normal hearing and simulated conductive hearing loss as the control groups conducted speech perception in noise (SPIN) and Gap-In-Noise (GIN) tests. The SPIN test asked how many presented sentences were understood at the +5 and -5 dB signal-to-noise ratio. The GIN test was asked to find the shortest gap in white noise with different lengths in the gap. Results: Compared to the groups with normal hearing and simulated instant hearing loss, the SSD group showed much poor performance in both SPIN and GIN tests while supporting central auditory plasticity of the SSD patients. Rather than a longer period of deafness, the large individual variance indicated that the congenital SSD patients showed better performance than the acquired SSD patients in two measurements. Conclusions: The results suggested that comprehensive assessments should be implemented before any treatment of the SSD patient considering their onset time and etiology, although these findings need to be generalized with a large sample size.

A Systematic Review and Meta-Analysis for Better Measurement of Listening Effort in Adults with Hearing Loss

곽찬범,한우재 한국청각언어재활학회 2021 Audiology and Speech Research Vol.17 No.1

The present study aimed to identify better tools for measuring listening effort in the hearing-impaired and/or hearing aid users and to suggest its clinical implication by using systematic review and meta-analysis. To search articles from six electronic databases, ‘listening effort’, ‘hearing loss/hearing impaired’, and ‘hearing aid(s)’ were used as their key terms. Although 8,761 articles were found initially, only 19 articles which met the inclusion criteria were applied to the further review and analysis. In a checklist of the study quality, there was no significant difference between the articles. Based on meta-analysis of three subgroups (i.e., objective, subjective, and self-report rating), the objective measurements showed statistically significant and the highest effect size (1.031, 95% confidence interval: -0.106-2.169), whereas the self-report rating had the lowest effect size (-1.280, 95% confidence interval: -4.180-1.620) with no significance. Although the funnel plot was asymmetrical, the Egger’s regression asymmetry test revealed no publication bias. In sum, the objective measurement showed the most effective way to evaluate the listening effort for the hearing-impaired and/or hearing aid users. However, there was a non-negligible variance between the types of measurements. In the following study, we suggest to investigate certain relationship between listening effort and speech perception performance in the hearing-impaired and/or hearing aid users and to establish standardized criteria for clinical purposes of the listening effort.

오차행렬과 Shepard’s 법칙을 적용한 말지각 지도 (NRF)

곽찬범,유성화,한우재,이동욱,마선미,박시훈,김여주 한국청각언어재활학회 2019 Audiology and Speech Research Vol.15 No.2

Purpose: To discriminate and/or perceive phonemes is one of the most important abilities in human communication. The purpose of current study was to measure the confusing matrix, similarity, and distance of Korean phonemes based on Shepard’s law and to provide Korean speech-perceptual map. Methods: To measure the similarity and distance, twenty young listeners with normal hearing conducted the speech discrimination task, which randomly assigned consonant-vowel (CV) combinations of 18 Korean consonants with /a/ vowel under quiet environment and two signal-to-noise ratio (SNR) noisy conditions (i.e., +3 and 0 dB SNR). The data of each participant was analyzed by classic confusion matrix. Based on the data of confusion matrix, the similarity and distance were calculated using the Shepard’s law. After calculating the distance, the speech-perceptual map was designated. Results: In general, the CV similarity was increased as a level of the background noise increased. The CV distance was also decreased as the noise levels increased. In quiet condition, only 18 pairs were showed confusing to discriminate. For the most confusing CV pair was /p/-/t/ which showed similarity of 0.14. With background noise, however, the +3 and 0 dB SNR conditions showed total 61 pairs and 64 pairs, respectively. The /ph/-/th/ was most confusing pair in both +3 (1.00 for similarity) and 0 dB SNR (0.98 for similarity). Conclusion: The results of current study suggest that the development of speech-perceptual map should be considered in the clinical settings in terms of rehabilitation for the hearing impaired listeners.

웹 기반 청능훈련 프로그램의 근접 분석: Toward Listening and Customized Learning Exercises for Aural Rehabilitation를 중심으로

곽찬범,김세아,한우재 대한이비인후과학회 2018 대한이비인후과학회지 두경부외과학 Vol.61 No.4

Aural rehabilitation is defined as a comprehensive service which includes hearing aid fitting, hearing aid orientation, auditory training, and informational/educational counseling for people with hearing loss in order to reduce deficits of auditory function, difficulty in communication, and limited social activity, and ultimately to enhance their quality of life. Although it is well known that auditory training among a large scope of the aural rehabilitation is critical to improve residual hearing of hearing-impaired adults and/or older adults, there are some limitations to conduct it in the clinic in terms of time consuming and individual difference. In this review paper, we introduce two of the most popular web-based auditory training programs, namely Listening and Communication Enhancement And customized learning: Exercises for Aural Rehabilitation. The paper analyzes their purpose, contents, effect (or benefit) of auditory training, and clinical application, while arguing their pros and cons. In conclusion, we discuss a necessary of developing auditory training platforms for the hearing-impaired adults and older adults, and then of forging systematic web-based auditory training tools with a low-cost and high efficiency because aging population is rapidly increasing in Korea.

한국스페셜올림픽대회 청각검진을 통해 바라본 지역건강돌봄: 강원도 인제

김세아,곽찬범,한우재 한국청각언어재활학회 2018 Audiology and Speech Research Vol.14 No.1

Intellectual disability is a disability characterized by significant limitations in both intellectual functioning and in adaptive behavior, which covers many everyday social and practical skills. Regardless of those limitations of people with intellectual disabilities, the first International Special Olympics Summer Games were held in July 1968, resulting from various movements for their equality and human right, and their social adaptation. Now, Special Olympics is the world’s largest sports organization for children and adults with intellectual disabilities, providing year-round training and competitions to 5.7 million athletes and Unified Sports partners in 172 countries including Korea. In particular, during the Olympic game, health athletes, which offers health screenings to athletes as need in seven areas: Fit Feet (podiatry), FUN fitness (physical therapy), Health Promotion (better health and well-being), Healthy Hearing (audiology), MedFest (sports physical exam), Opening Eyes (vision), and Special Smiles (dentistry). Among them, the Healthy Hearing program includes otoscopy, otoacoustic emission, tympanometry, pure-tone screening, and pure-tone threshold tests, to inform hearing status and additional management for the athletes. This brief communication presents history and principle of Special Olympics including its development in Korea. Also it offers useful information for the athletes participating in the Special Olympics, who have intellectual disability, to understand them, while reporting brief outcomes of healthy hearing program of the Special Olympic Korea held in Inje, Gangwon. In final part of this brief communication, we scrutinize hearing status of people with intellectual disabilities who live in Inje, Gangwon in terms of local healthcare. In closing, we request professional attention and care to them as audiology and speech-language specialists as well as readers of Audiology and Speech Research.

Better Understanding of Direct Bone-Conduction Measurement: Comparison with Frequency-Specific Bone-Conduction Tones and Brainstem Responses

김여주,한우재,박시훈,유성화,곽찬범,서영준,이지현 대한청각학회 2020 Journal of Audiology & Otology Vol.24 No.2

Background and Objectives: The present study aimed to compare thresholds of direct bone-conduction (BC direct) with those of behaviorally measured BC pure-tone audiometry (PTA) and objectively measured BC auditory brainstem response (ABR) to confirm the clinical feasibility of their relationships. Subjects and Methods: Young adults with normal hearing participated in the study to determine the thresholds from three measurements at four testing frequencies. In the BC direct, the vibrator of a bone-anchored hearing aid softband was placed on the right mastoid of each subject. In both PTA and ABR, a B71 bone oscillator was placed on the subject’s right mastoid. While the subject’s thresholds of BC direct and BC PTA were determined with a clinically routine 5-dB step procedure, BC ABR was conducted to determine the individual’s hearing sensitivity by a peak V of the waveform using tone-burst and click stimuli. Results: The BC direct showed a different pattern between low and high frequencies. Precisely, its thresholds were 13.25 and 12.25 dB HL at 0.5 and 1 kHz, respectively, but 19 and 19.75 dB HL at 2 and 4 kHz, respectively. A significant positive correlation existed between BC direct and PTA at 1 kHz, which was also correlated with ABR. Conclusions: Based on the current data, the thresholds of BC direct were similar to BC PTA at low frequencies and BC ABR at high frequencies. The thresholds of BC direct might be predictable at approximately 5 dB higher (or lower) than that in PTA, although a large data set is required for standardization.

소음성 난청의 효율적인 예방을 위한 첨도 측정법의 이해

유성화(Sunghwa You),곽찬범(Chanbeom Kwak),김세아(Saea Kim),이장원(Jangwon Lee),정승엽(Seungyeop Jeong),이은성(Eunsung Lee),송현욱(Hyunwook Song),Nour Alsabbagh,한우재(Woojae Han) 한국청각언어재활학회 2018 Audiology and Speech Research Vol.14 No.3

Purpose: In general, energy metrics, i.e., LAeq 8 hours, have been applied as a risk indicator of noise exposure. However, there are some limitations of LAeq measurement since it considers only the amount of average energy of noise and is not appropriate for measuring the complex noise. In light of this, the kurtosis metrics have been introduced by many contemporary researchers to be applied as an alternative measure. Methods: In the main body, we introduced the weakness of current noise exposure criteria, compared between Gaussian and non-Gaussian noise, briefly explained the concepts of kurtosis metrics, and scrutinized more applications of the kurtosis metrics by summarizing previous 7 research papers. Results: Compare to the Gaussian noise, the non-Gaussian noise has been found to have stronger cochlear damage effects on the outer and inner hair cells and led to permanent hearing loss in the higher frequencies. Noise exposure trauma levels were dramatically increased as the kurtosis levels increased. Although kurtosis metrics are a good indicator or measure, it still need to be adjusted in terms of frequency-specificity. Conclusion: Since the kurtosis metrics are not implemented in Korea, especially in the industrial field, we need to develop a new measurement approach using the kurtosis metrics on workers and then provide scientific based criteria for effectively preventing their potential risk of developing noise-induced hearing loss.

Effect of Speech Degradation and Listening Effort in Reverberating and Noisy Environments Given N400 Responses

Kyong Jeong-Sug,곽찬범,Han Woojae,서명환,김진숙 대한청각학회 2020 Journal of Audiology & Otology Vol.24 No.3

Background and Objectives: In distracting listening conditions, individuals need to pay extra attention to selectively listen to the target sounds. To investigate the amount of listening effort required in reverberating and noisy backgrounds, a semantic mismatch was examined.Subjects and Methods: Electroencephalography was performed in 18 voluntary healthy participants using a 64-channel system to obtain N400 latencies. They were asked to listen to sounds and see letters in 2 reverberated×2 noisy paradigms (i.e., Q-0 ms, Q-2000 ms, 3 dB-0 ms, and 3 dB-2000 ms). With auditory-visual pairings, the participants were required to answer whether the auditory primes and letter targets did or did not match. Results: Q-0 ms revealed the shortest N400 latency, whereas the latency was significantly increased at 3 dB-2000 ms. Further, Q-2000 ms showed approximately a 47 ms delayed latency compared to 3 dB-0 ms. Interestingly, the presence of reverberation significantly increased N400 latencies. Under the distracting conditions, both noise and reverberation involved stronger frontal activation. Conclusions: The current distracting listening conditions could interrupt the semantic mismatch processing in the brain. The presence of reverberation, specifically a 2000 ms delay, necessitates additional mental effort, as evidenced in the delayed N400 latency and the involvement of the frontal sources in this study.

최신 청력보호장비의 종류와 적용

송현욱,정승엽,이은성,Nour Alsabbagh,이장원,유성화,곽찬범,김세아,한우재 대한이비인후과학회 2019 대한이비인후과학회지 두경부외과학 Vol.62 No.1

Since noise-induced hearing loss (NIHL) is one of prevalent issues in the occupational settings,hearing protection device (HPD) has been widely used to reduce noise exposure levelsand to prevent developing NIHL. This review study aimed to introduce several types of theHPD in terms of current trends, its variety and functions, and application. Including a briefhistory of the HPD, we explain its two types, i.e., passive and active functions, in the first part ofmain body. The passive HPD has a flat attenuation across the overall frequency range, whereasthe active HPD effectively preserves communication components such as meaningful speechwith low intensity stimuli while filtering out the high levels of noise. In the second part of themain body, we discuss some negative issues of hearing functions when users are wearing theHPD. In detail, the active HPD does not much degrade the hearing performance for speechdetection/recognition and sound source localization compared to the passive HPD. Rather, reducedsound (or music) quality is improved with active one in general. In the final part, wemention that although various applications in the special fields such as factory, mining, army,airplane, and music have been demonstrated, the usage and awareness of HPD in occupationalaspect may not follow its fast technological development. Furthermore, most people do notknow about either importance or use method of HPD in the non-occupational setting. For thesereasons, we conclude that hearing professionals have to access the latest trends of the HPDand to increase their knowledge on it, and thus they should provide the best HPD prescriptionfor the public as well as employees who have to protect their ears from hazard noise impacts.