귀 외이도의 Resonant Frequency에 대한 분석

최철희,김기홍,천권수 한국물리학회 2012 새물리 Vol.62 No.2

We investigated the effects of various variables on the resonant frequency of the external ear canal through a mathematical analysis. Basically, the external ear canal receives and directs acoustic sounds to the tympanic membrane and provides protection for the tympanic membrane against insects and other foreign bodies. We accomplished a mathematical analysis of the resonant frequency of the external ear canal by using the mass, the stiffness, and damping (resistance). The resonant frequency was proportional to the stiffness and inversely proportional to the mass. The resonant frequency was determined by a combination of the reactance (X) and the resistance(R). When the mass reactance was equal to the stiffness reactance, the resonant frequency was determined by only the resistance. Regions below the resonant frequency were stiffness-dominated while regions above the resonant frequency were mass-dominated. Furthermore, the resonant frequency was controlled by other variables such as the bandwidth, the length, and the power. This study provides a quantitative method to analyze the resonant frequency of the external ear canal and predicts changes induced in the resonant frequency by changes in the acoustic characteristics of the external ear canal. 귀의 외이도의 resonant frequency에 영향을 미치는 다양한 변인들을수학적인 분석을 통해 찾고자 하였다. 기본적으로 귀의 외이도는음향학적인 신호를 고막에 전달하는 채널로 중요한 역할을 수행한다. 귀의 외이도의 resonant frequency는 기본적으로 mass, stiffness,그리고 damping(resistance)를 통해 모델링을 할 수 있었다. Mass와stiffness는 저항의 한 종류인 reactance를 구성하는데 이를 mass reactance와 stiffness reactance로 부른다. 수학적 모델의 결과로resonant frequency는 reactance와 resistance에 의해 결정되는데stiffness reactance와 mass reactance가 서로 같아서 상쇄될 때resistance에 의해서만 결정되었다. Resonant frequency보다 적은주파지역은 stiffness에 의해 지배되고 resonant frequency 보다 높은주파지역은 mass에 의해 지배되었다. 게다가 resonant frequency는bandwidth, length, 그리고 power에 의해 영향을 받았다. 따라서 본연구는 외이도의 resonant frequency를 양화할 수 있는 좋은 방법을제시하여 외이도의 음향학적 변화에 따라 resonant frequency의 변화를예측가능하게 한다.

외이도에 단독으로 발생한 점액종: 증례 보고

박아름,김태규,김현정,조우호,김재형,정명자,김성희,김지영,김수현,강미진,이지혜,배경은 대한영상의학회 2018 대한영상의학회지 Vol.79 No.2

Myxoma is a benign mesenchymal neoplasm found in the heart, bone, and other soft tissues. However, myxoma of the external auditory canal is extremely rare. Since myxoma of the external auditory canal can be manifested as a part of the Carney complex, an autosomal dominant multiple familial neoplastic disorder, correct diagnosis and thorough investigation is important. We report a case of a 59-year-old man who presented to hospital with a complaint of growing mass within the right external auditory canal during one month. The surgical excision was done, and the histopathological examination revealed myxoma. In this article, we report the magnetic resonance imaging and computed tomography findings of the myxoma of the external auditory canal and correlate with the histopathological finding. 점액종은 양성 중간엽종양으로서 심장, 뼈를 비롯한 연부조직에서 생길 수 있지만 외이도에서 발생하는 경우는 극히 드물다. 한편, 외이도의 점액종은 상염색체 우성으로 유전되는 다수의 가족성 종양 증후군인 Carney 복합체(complex)의 한부분으로 발현될 수 있기 때문에 진단 및 철저한 조사가 중요하다. 본 증례에서 59세 남성 환자가 한 달 전부터 발생해서점점 커지는 양상의 오른쪽 외이도 종괴를 주소로 내원하였고, 수술적 절제 후 조직병리검사 결과 점액종으로 확진되었다. 본 증례는 외이도 점액종의 자기공명영상 및 전산화단층촬영 소견을 보고하고, 조직병리 소견과 관련해서 이해해 보고자 한다.

실이에서 여자 음성 /ㅏ/, /ㅣ/, /ㅜ/의 포먼트 주파수 변화

허승덕(Heo, Seungdeok),강희라(Kang, Huira) 한국음성학회 2017 말소리와 음성과학 Vol.9 No.1

Formant frequencies depend on the position of tongue, the shape of lips, and larynx. In the auditory system, the external ear canal is an open-end resonator, which can modify the voice characteristics. This study investigates the effect of the real ear on formant frequencies. Fifteen subjects ranging from 22 to 30 years of age participated in the study. This study employed three corner vowels: the low central vowel /a/, the high front vowel /i/, and the high back vowel /u/. For this study, the voice of a well-educated undergraduate who majored in speech-language pathology, was recorded with a high performance condenser microphone placed in the upper pinna and in the ear canal. Paired t-test showed that there were significant difference in the formant frequencies of F1, F2, F3, and F4 between the free field and the real ear. For /a/, all formant frequencies decreased significantly in the real ear. For /i/, F2 increased and F3 and F4 decreased. For /u/, F1 and F2 increased, but F3 and F4 decreased. It seems that these voice modifications in the real ear contribute to interpreting voice quality and understanding speech, timbre, and individual characteristics, which are influenced by the shape of the outer ear and external ear canal in such a way that formant frequencies become centralized in the vowel space.

Influence of Real Ear Resonance on Male Voice Formant Frequency

허승덕(Seung Deok Heo),강희라(Hui Ra Kang),고도흥(Do Heung Ko) 한국언어청각임상학회 2017 Communication Sciences and Disorders Vol.22 No.3

배경 및 목적: 소리는 음장을 지나 외이도, 중이, 내이 등으로 상행한다. 외이도는 음향에너지 특성이 유지되는 곳으로 공명에 의해 말소리의 음향학적 특성이 달라질 것으로 예상된다. 이 연구는 실이에서 음성의 포먼트 주파수를 분석하여, 외이 공명이 음성에 어떤 영향을 미치는지 알아보는데 목적이 있다. 방법: 모음은 사용 빈도가 높은 /ㅏ/, /ㅣ/, /ㅜ/, /ㅔ/, /ㅗ/를 사용하였다. 음성은 남자가 발성하여 여자 12명의 외이도 내부와 이개 상부에서 각각 녹음하였다. 이들 음성은 포먼트 주파수를 분석한(Praat ver. 6.0.19) 후 기술통계 하였고, 대응표본 t-test (SPSS ver. 22.0)와 Wilcoxon test로 검증하였다. 결과: 음장과 실이 음성 사이에서는 /ㅏ/의 F3, F4, /ㅣ/의 F2, F3, F4, /ㅜ/의 모든 포먼트 주파수, /ㅔ/의 F2, F4, /ㅗ/의 F1, F3, F4 등에서 통계적으로 유의한 차이가 관찰되었다(p<.05). 논의 및 결론: 실이 음성의 포먼트 주파수는 공명, 음원으로부터 거리 등의 영향을 받아 주파수가 모아진다. 이러한 변화는 음색 및 개인 목소리의 특성을 해석하고 어음을 이해하는데 긍정적인 영향을 줄 것으로 기대된다. Objectives: Voice in the external auditory canal (EAC) is expected to change while being affected by the resonance of the concha cavity and the EAC. Acoustical analysis should include the frequency range of EAC resonance. This study aims to determine the influence of the resonance of the EAC by analyzing formant. Methods: Male voiced monophthongs were used in this study; the most frequently used vowels were /a/, /i/, /u/, /e/, /o/. Experimental voice in the real ear and sound field was recorded by 12 healthy young female subjects. Voice characteristics were analyzed by Praat (ver. 6.0.19). The formant frequency of the sample and experimental voice were analyzed with descriptive statistics. The relationship between the sample voice and experimental voice was analyzed by a paired t-test. Results: The voices between the sound field and real ear demonstrated significant differences at F3 and F4 of /a/, F2, F3, and F4 of /i/, all formant frequencies of /u/, F2 and F4 of /e/, and F1, F3, and F4 of /o/ (p<.05). Conclusion: Voice in the real ear is collected under the influence of resonances, distance from the sound source, and rounding. Understanding these changes is expected to improve the analysis of timbre and individual voices and speech understanding.

순수 외이도 공명

허승덕(Seung Deok Heo) 한국언어치료학회 2012 言語治療硏究 Vol.21 No.3

External auditory canal (EAC) resonance occurs in the closed-end of a tube near the ear drum. However, the gain of EAC resonance cannot be measured because it occurs inside the human body. Real ear unaided responses (REURs) include both the acoustic reflection of the pinna, skull, torso and the resonance gain of the external ear. The concha cavity resonance (CC resonance) can be measured if EAC is obstructed. Therefore, EAC resonance can be calculated by subtracting the CC resonance from REURs. The aim of this study is to find the gain of the EAC resonance in normal Korean adults and provide the basic information for hearing aid fitting and further research in the field of audiological rehabilitation. Twenty-none normal adults (58-ears) participated in this study. The frequency range of EAC resonance was observed from 80㎐ to 4,000㎐ at 0° and from 600㎐ to 3,700㎐ at 45°. The maximum resonance frequency was recorded at 2,619(±288.7)㎐ at azimuth 0° and 2,613.8(±381.8)㎐ at azimuth 45°. The mean of maximum resonance gain was recorded at 13.2(±3.5)㏈ and 12.3(±3.4)㏈, respectively.

아놀드 신경에서 발생한 외이도의 신경초종 1예

이오형,박정미,한정주,박시내 대한이비인후과학회 부산,울산,경남 지부회 2018 임상이비인후과 Vol.29 No.2

Neurilemmoma is a benign tumor that originates from the Schwann cell. It frequently occurs in head and neck regions, but neurilemmoma of external auditory canal is extremely rare. Here, we report a very rare case of 36-yearold male with a tumor located in the posterior wall of external auditory canal, preoperatively suspected as neurilemmoma originated from Arnold’s nerve by temporal bone magnetic resonance imaging. The tumor mass was surgically excised and pathologically confirmed as a neurilemmoma