VA RR&D National Center for Rehabilitative Auditory Research (NCRAR), VA Portland Health Care System, Portland, Oregon, USA.
Department of Otolaryngology/Head and Neck Surgery, Oregon Health & Science University, Portland, Oregon, USA.
Ear Hear. 2018 Sep/Oct;39(5):881-894. doi: 10.1097/AUD.0000000000000544.
To determine whether auditory brainstem response (ABR) wave I amplitude is associated with measures of auditory perception in young people with normal distortion product otoacoustic emissions (DPOAEs) and varying levels of noise exposure history.
Tinnitus, loudness tolerance, and speech perception ability were measured in 31 young military Veterans and 43 non-Veterans (19 to 35 years of age) with normal pure-tone thresholds and DPOAEs. Speech perception was evaluated in quiet using Northwestern University Auditory Test (NU-6) word lists and in background noise using the words in noise (WIN) test. Loudness discomfort levels were measured using 1-, 3-, 4-, and 6-kHz pulsed pure tones. DPOAEs and ABRs were collected in each participant to assess outer hair cell and auditory nerve function.
The probability of reporting tinnitus in this sample increased by a factor of 2.0 per 0.1 µV decrease in ABR wave I amplitude (95% Bayesian confidence interval, 1.1 to 5.0) for males and by a factor of 2.2 (95% confidence interval, 1.0 to 6.4) for females after adjusting for sex and DPOAE levels. Similar results were obtained in an alternate model adjusted for pure-tone thresholds in addition to sex and DPOAE levels. No apparent relationship was found between wave I amplitude and either loudness tolerance or speech perception in quiet or noise.
Reduced ABR wave I amplitude was associated with an increased risk of tinnitus, even after adjusting for DPOAEs and sex. In contrast, wave III and V amplitudes had little effect on tinnitus risk. This suggests that changes in peripheral input at the level of the inner hair cell or auditory nerve may lead to increases in central gain that give rise to the perception of tinnitus. Although the extent of synaptopathy in the study participants cannot be measured directly, these findings are consistent with the prediction that tinnitus may be a perceptual consequence of cochlear synaptopathy.
确定在具有正常畸变产物耳声发射（DPOAE）和不同噪声暴露史的年轻人中，听觉脑干反应（ABR）I 波幅度是否与听觉感知测量值相关。
对 31 名年轻的退伍军人和 43 名非退伍军人（年龄在 19 至 35 岁之间）进行了耳鸣、响度耐受和言语感知能力的测量，这些参与者的纯音阈值和 DPOAE 均正常。言语感知在安静环境中使用西北大学听觉测试（NU-6）单词列表进行评估，在噪声环境中使用单词在噪声中（WIN）测试进行评估。使用 1、3、4 和 6 kHz 脉冲纯音测量响度不适水平。在每位参与者中收集 DPOAE 和 ABR，以评估外毛细胞和听神经功能。
在调整性别和 DPOAE 水平后，该样本中报告耳鸣的概率男性每降低 0.1 µV 的 ABR I 波幅度增加 2.0 倍（95%贝叶斯置信区间，1.1 至 5.0），女性增加 2.2 倍（95%置信区间，1.0 至 6.4）。在调整性别、DPOAE 水平和纯音阈值的另一个模型中，也得到了类似的结果。在安静或噪声环境中，I 波幅度与响度耐受或言语感知均无明显关系。
即使在调整了 DPOAE 和性别后，ABR I 波幅度降低与耳鸣风险增加相关。相比之下，III 波和 V 波幅度对耳鸣风险的影响较小。这表明在毛细胞或听神经水平的外周输入变化可能导致中枢增益增加，从而产生耳鸣的感知。虽然研究参与者的突触病程度无法直接测量，但这些发现与耳鸣可能是耳蜗突触病的知觉后果的预测一致。
