정상 한국인의 수평형 음방위 판별에 관한 연구

A Study of Horizontal Sound Localization Ability in Normal Koreans

정상 한국인의 수평면에서의 위치판별에서 자극음, 성, 연령, 방향별 영향력의 유무를 기록하고 효과적 자극음을 검증하고자 했다. 49명의 정상인을 대상으로 자극 음으로는 speech noise, ⅓ octave narrow band noise centered at 500 Hz, 4000 Hz & pure tone 500 Hz, 4000 Hz를 사용한 결과 동일한 음자극에서는 고주파수보다 저주파수에서 방향판별력이 우수했고 pure tone보다는 narrow band noise로 자극했을때 narrow band noise보다는 speech noise로 자극했을 때, 방향판별력이 우수한 것으로 나타났다. 성별이나 연령의 영향은 받지 않았으며 전후좌우를 비교했을 때는 좌측판별력이 우수한 것으로 나타났다.

Sound localization ability is a complex phenomenon resulting from the interaction between the two ear s . Sound localization is possible because of the relative intensity of sound and it s time of arrival at two ear s. T he greatest single contributor s for localizing sound are interaural time disparity in the low frequency (below 1500 Hz) and intensity differences in the high ferquency (above 2000 Hz). T he effect s of the stimulus type, gen - der , age, and direction were ex amined. T his reserch was performed in a nonreberverant room with 49 normal korean subject s aging between 10 to 50. Laudspeaker s which presented the stimuli are located at azimuth angles in 45°increment s around the head. Speech noise, 1/ 3 octave narrow band noise centered at 500 Hz and 4000 Hz, and pure tone 500 Hz and 4000 Hz were used as stimuli. T he result s showed that speech noise was the best stimulu s for localizing sound. Directional discrimination score was very poor in pure tone 4000 Hz group. T here were no significant differences in directional discrimination range among ages and gender s. Front - back of azimuth angle in direction didn t show any differences, but left discrimination was relatively better than right in all stimulus type ex cept NBN 500 Hz. Conclusively, speech noise was the most reliable for sound localization and the low frequency was more reliable than the high frequency for the directional discrimination when u sing a similar stimulus type. T he result s seems to be valuable in evaluation of hearing aid properties and aural rehabilitation.