耳聲傳射的對側抑制與噪音下聽辨測驗之探討

聽力正常者在噪音下也可能遭遇聆聽困難，聽覺傳出系統中的內側橄欖耳蝸（MOC）的抑制作用對語音的辨識具有關鍵功能。本研究使用變頻耳聲傳射對側抑制值評估內側橄欖耳蝸的運作，搭配台灣版華語噪音下語音辨識測驗（MHINT-T）探討內側橄欖耳蝸限制外毛細胞的活動度與噪音下語音辨識表現的關聯。　　本研究受試者為聽力正常之年輕成人45位，年齡介於20至29歲。紀錄受試者DPOAE加入對側抑制音前、後的有效反應振幅相減計算抑制值，並與MHINT-T之訊噪比進行皮爾森相關和回歸分析。　　研究結果唯有右耳F2 = 6000 Hz的DPOAE對側抑制值與MHINT-T訊噪比達顯著低度正相關，其它頻率之DPOAE對側抑制值在統計上均與MHINT-T訊噪比無顯著相關亦無顯著預測作用。

People with normal hearing may experience hearing difficulties in noise. The medial olivocochlear in the auditory efferent system plays a crucial role in speech-in-noise discrimination. This study assesses MOC functioning by measured contralateral suppression (CS) of DPOAE, and Mandarin Hearing In Noise Test in Taiwan (MHINT-T) to investigate the relationship between the performance of speech recognition in noise and MOC limiting the micromechanics of the outer hair cells. The study was performed on 45 young adults with normal hearing between the ages of 20 and 29 years (mean 22.1 years). The DPOAE suppression value for each subject was calculated by subtracting the recorded amplitude with and without CS which was analyzed via Pearson correlation and regression analysis with the signal-to-noise ratio (SNR) of MHINT-T. The results showed that only CS of DPOAE with F2= 6000 Hz in the right ear had a significant low positive correlation with the MHINT-T SNR. The remaining statistical data CS of DPOAE for right, left or both ears at individual frequencies or overall frequencies are not statistically significantly related to, and have no predictive effect to the MHINT-T SNR.