In-Ki Jin

Derivations of the band-importance function: A cross-procedure comparison

The purpose of this study was to compare band-importance functions (BIFs) derived by two different procedures. Intelligibility data from native speakers of Korean were used. BIFs were derived using an established procedure reported by Studebaker and Sherbecoe [J. Speech Lang. Hear. Res. 34, 427-438 (1991)] and by a recently published method reported by Kates [J. Acoust. Soc. Am. 134(5), EL459-EL464 (2013)]. The BIFs produced by the two different procedures were similar. These results indicate that the BIF calculation procedure by Kates is accurate for sentences as well as for the monosyllables used in its derivation.

Dynamic Range for Speech Materials in Korean, English, and Mandarin: A Cross-Language Comparison

PURPOSE The purpose of this study was to identify whether differences in dynamic range (DR) are evident across the spoken languages of Korean, English, and Mandarin. METHOD Recorded sentence-level speech materials were used as stimuli. DR was quantified using different definitions of DR (defined as the range in decibels from the highest to the lowest signal intensities), for several integration times (from 1 to 512 ms) and in different frequency bands (center frequencies [CFs] ranging from 150 to 8600 Hz). RESULTS Across the 3 languages, DR was affected in similar ways with regard to changes in DR definition and integration time. In contrast, across-language differences in DR were evident when considering frequency-band effects. Specifically, the DR for Korean was smaller than the English DR and the Mandarin DR in low-frequency bands (less than the CF of 455 Hz). Compared with Korean and Mandarin, the DR for English was smallest in mid-frequency bands (between the CF of 455 Hz and 4050 Hz) and was greatest in high-frequency bands (above the CF of 4050 Hz). CONCLUSION The observed differences in DR across languages suggest that the best-fit DR for Korean and Mandarin may be different than the best fit for English.

Sensitivity of the Speech Intelligibility Index to the Assumed Dynamic Range

Purpose This study aims to evaluate the sensitivity of the speech intelligibility index (SII) to the assumed speech dynamic range (DR) in different languages and with different types of stimuli. Method Intelligibility prediction uses the absolute transfer function (ATF) to map the SII value to the predicted intelligibility for a given stimuli. To evaluate the sensitivity of the predicted intelligibility to the assumed DR, ATF-transformed SII scores for English (words), Korean (sentences), and Mandarin (sentences) were derived for DRs ranging from 10 dB to 60 dB. Results Increasing the assumed DR caused steeper ATFs for all languages. However, high correlation coefficients between predicted and measured intelligibility scores were observed for DRs from 20 dB to 60 dB for ATFs in English, Korean, and Mandarin. Conclusions Results of the present study indicate that the intelligibility computed from the SII is not sensitive to the assumed DR. The 30-dB DR commonly used in computing the SII is thus a reasonable assumption that produces accurate predictions for different languages and different types of stimuli.

The effect of noise envelope modulation on quality judgments of noisy speech

This study aims to evaluate how speech quality is affected by noise which varies in modulation from 0% (the lowest correlation with the speech envelope) to 100% (the highest correlation with the speech envelope). Using a scaled paired-comparison forced-choice procedure, ten normal-hearing listeners rated overall preference, noisiness, and distortion of speech stimuli with different noise modulation percentages at 0, 10, and 20 dB signal-to-noise ratios. As noise modulation percentage increased, ratings for overall preference increased, ratings for distortion increased, and ratings for noisiness decreased. The noise modulation effects on quality ratings were significant, even at the same signal-to-noise ratio.

Acoustic Features and Cortical Auditory Evoked Potentials according to Emotional Statues of /u/, /a/, /i/ Vowels

Background and Objectives Although Ling 6 sounds are often used in the rehabilitation process, its acoustic features have not been fully analyzed and represented in cortical responses. Current study was aimed to analyze acoustic features according to gender and emotional statuses of core vowels of Ling 6 sounds, /u/, /a/, and /i/. Cortical auditory evoked potentials (CAEPs) were also observed in those vowels. Subjects and Methods Vowel sounds /u/, /a/, and /i/ out of Ling 6 sounds representing low, middle and high frequencies were recorded from normal 20 young adults. The participants watched relevant videos for 4-5 minutes in order for them to sympathize emotions with anger (A), happiness (H), and sadness (S) before producing vowels. And without any emotional salience, neutrally production was performed. The recording was extracted for 500 ms to select pure vowel portion of production. For analysis of CAEP, the latencies and amplitudes of P1, N1, P2, N2, N1-P2 were analyzed. Results Intensities of /u/, /a/, and /i/ were 61.47, 63.38, and 60.55 dB. The intensities of neutral (N), H, A, S were 60.60, 65.43, 64.21, and 55.75 dB for vowel /u/, vowel /a/ were 61.80, 68.98, 66.50, and 56.23 dB, and vowel /i/ were 59.34, 64.90, 61.90, and 56.05 dB. The statistical significances for vowel and emotion were found but not for gender. The fundamental frequency (F0) of vowels for N, A, H, and S were 168.04, 174.93, 182.72, and 149.76 Hz and the first formant were 743.75, 815.59, 823.32, and 667.62 Hz. The statistical significance of F0 was found by vowel, emotion, and gender. The latencies and amplitudes of CAEP components did not show any statistical significance according to vowel. Conclusions Ling 6 sounds should be produced consistently in the rehabilitation process for considering their difference of intensities and frequencies according to speaker’s emotions and gender. The vowels seemed to be interpreted as tonal stimuli for CAEP components of this study with similar acoustic features among them. Careful selection of materials is necessary to observe meaningful conclusion of CAEP measurement with vowel stimuli.

Author's Rebuttal to Smits et al. (2017), “Comment on ‘Sensitivity of the Speech Intelligibility Index to the Assumed Dynamic Range’ by Jin et al. (2017)”

Purpose The purpose of this letter is to refute the comments written by Smits, Goverts, and Versfeld (2018). Method Refutations to each issue including the fixed mathematical relationship between dynamic range (DR) and a fitting constant (Q value), deviating results for small DRs, and determination of Speech Intelligibility Index (SII) model parameters are described. Results Although Smits et al. (2018) correctly identified several issues, those comments do not diminish the results of the original article (Jin, Kates, & Arehart, 2017) in providing new insights for the SII. Conclusions Jin et al. (2017) clearly provided the impact of languages and DR on the SII, which was the main result of the study.

Does Language Matter When Using a Graphical Method for Calculating the Speech Intelligibility Index

Background: Graphical methods for calculating the speech intelligibility index (SII), such as the count‐the‐dot audiogram, are useful tools in quantifying how much weighted audibility is restored when amplification is used for individuals with hearing loss. The band‐importance function (BIF), which is an important component of the SII, depends on the language. Thus, language may affect the prediction of weighted audibility using the graphical SII. Purpose: The purpose of this study was to apply language‐specific BIFs to develop and compare graphical SIIs for English, Korean, and Mandarin. Research Design: The graphical SIIs were developed and compared using a research design that applied and analyzed existing datasets. Data Collection and Analysis: Language‐specific BIFs and dynamic ranges were used to derive graphical SIIs for English, Korean, and Mandarin. SII predictions were compared by calculating the language‐specific predictions for the same audiometric configurations. Results: The graphical SIIs for English, Korean, and Mandarin yielded different unaided and aided predictions for the same audiogram configurations. Conclusions: A graphical SII helps patients easily understand their weighted audibility for unaided and aided conditions; thus, it is a useful counseling tool in the clinic. The most accurate graphical SIIs will, however, be based on a patients spoken language.

Substitution Patterns of Phoneme Errors in Hearing Aid and Cochlear Implant Users

Background and Objectives It is acknowledged that speech perceptual errors are increased in listeners who have sensorineural hearing loss as noise increases. However, there is a lack of detailed information for their error pattern. The purpose of the present study was to analyze substitution patterns of phoneme errors in Korean hearing aid (HA) and cochlear implant (CI) users who are postlingually deafened adults. Subjects and Methods In quiet and under two noise conditions, the phoneme errors of twenty HA and fourteen CI users were measured by using monosyllabic words, and a substitution pattern was analyzed in terms of manner of articulation. Results The results showed that both groups had a high percentage of nasal and plosive substitutions regardless of background conditions. Conclusions This finding will provide vital information for understanding the speech perception of hearing-impaired listeners and for improving their ability to communicate when applied to auditory training.

Understanding of Clear Speech and Suggestions for Clinical Applications

클리어스피치(clear speech)는 청자의 대화 이해도를 높이기 위한 어음 발성법으로서 말소리 산출 속도(speech rate)의 감 소, 음의 높낮이(pitch) 범위 확장, 중요 어휘의 강도(intensity) 증가를 통한 음향학적 조음 수정 전략을 의미한다(Smiljanic & Bradlow, 2007). 난청자를 위한 의사소통 전략으로 제안되기 이전에 클리어스 피치는 군사용 음성송수신기기의 사용 시에 명료한 음성을 전 달하기 위한 발성법으로 사용되어 왔다(Snidecor et al., 1944). 주로 적용된 방법은 발성 속도를 늦추고 조음을 정확하게 하도 록 훈련하는 것이었으며, 최대 9%까지 어음인지도(speech intelligibility) 가 향상될 수 있다고 보고하였다(Tolhurst, 1957). 이후 여러 연구자들에 의하여 클리어스피치는 난청자의 어음 인지도 향상을 위한 의사소통 전략으로 제안되어 왔다(Caissie & Tranquilla, 2010; Picheny et al., 1985).

Rehabilitation Options for Subjective Tinnitus

이명(tinnitus)은 라틴어 ‘Tinnire’에서 유래한 이름으로 ‘Tinnire’ 는 ‘울리다’라는 뜻으로 외부로부터 소리 자극이 없음에도 불구하고 주관적으로 소리를 지각하는 것을 의미한다(Jastreboff, 1990). 기원전 16세기 이집트 17대 왕조 시대 에버스 파 피루스에서는 ‘귀에서 윙윙거리는 소리’로 이명을 기술한 기록 이 발견되었으며(Kraft, 1998), 기원전 17세기 앗시리아인의 점 토판에서는 이명을 ‘노래를 부르는 형태’, ‘속삭이는 형태’ 그리 고 ‘말하는 형태’ 3가지로 분류하였고 각기 다른 치료법이 필요 하다고 기술한 기록이 발견되었다(Yeo, 2011). 고대로부터 시작 된 이명의 치료에 관한 연구는 명확한 기전의 발견을 위해 현재 까지도 활발한 연구가 진행 중이며, 미국, 영국, 호주 등 세계 여 러 나라에서 이명협회가 조직되어 이명의 치료 방법을 연구하거나 이명의 효과적인 관리를 위한 정보를 제공하고 있다. 또한 이명연구선도회(Tinnitus Research Initiative)와 같은 국제 이 명연구단체가 조직되어 이명과 관련된 전문가들이 공동으로 이명의 원인과 재활법에 대한 연구를 진행하고 있다(Kim et al., 2015).이명(tinnitus)은 라틴어 ‘Tinnire’에서 유래한 이름으로 ‘Tinnire’는 ‘울리다’라는 뜻으로 외부로부터 소리 자극이 없음에도 불구하고 주관적으로 소리를 지각하는 것을 의미한다(Jastreboff, 1990). 기원전 16세기 이집트 17대 왕조 시대 에버스 파 피루스에서는 ‘귀에서 윙윙거리는 소리’로 이명을 기술한 기록 이 발견되었으며(Kraft, 1998), 기원전 17세기 앗시리아인의 점 토판에서는 이명을 ‘노래를 부르는 형태’, ‘속삭이는 형태’ 그리 고 ‘말하는 형태’ 3가지로 분류하였고 각기 다른 치료법이 필요 하다고 기술한 기록이 발견되었다(Yeo, 2011). 고대로부터 시작 된 이명의 치료에 관한 연구는 명확한 기전의 발견을 위해 현재 까지도 활발한 연구가 진행 중이며, 미국, 영국, 호주 등 세계 여 러 나라에서 이명협회가 조직되어 이명의 치료 방법을 연구하 거나 이명의 효과적인 관리를 위한 정보를 제공하고 있다. 또한 이명연구선도회(Tinnitus Research Initiative)와 같은 국제 이 명연구단체가 조직되어 이명과 관련된 전문가들이 공동으로 이명의 원인과 재활법에 대한 연구를 진행하고 있다(Kim et al., 2015). 이명의 유병률은 국가마다 차이는 있지만 비교적 높은 유병 률을 보인다. 미국이명협회에서 보고한 이명 유병률에 따르면 20세부터 69세 사이 인구의 15%인 약 5,000만명 정도가 이명 환자인 것으로 보고하였으며, 그 중 2,000만명은 만성이명을, 200만명 정도는 매우 심한 이명을 경험하고 있다고 보고하였다 (American Tinnitus Association, 2014). 또한 2013년 영국이명협 회 연차보고서에 따르면, 영국의 경우 성인의 10%가 이명을 가 지고 있으며, 그 중 10%는 우울증, 스트레스, 수면 방해 등으로 인해 심한 고통을 받고 있다고 보고하였다(British Tinnitus AsRehabilitation Options for Subjective Tinnitus Dongchang Kim, Jinbae Shin, Kyungju Lee, In-Ki Jin Department of Speech Pathology and Audiology, Graduate School, Hallym University, Chuncheon, Korea Division of Speech Pathology and Audiology, Research Institute of Audiology and Speech Pathology, College of Natural Science, Hallym University, Chuncheon, Korea