BINAURAL HEARING BEFORE AND AFTER MIDDLE EAR SURGERY

这个项目的长期目标是一个更好的 对传导性听力损失影响的认识 成人和儿童的双耳听力。的第一个目标是 本项目将调查导致贫困的因素 成人传导性病变的掩蔽水平差异表现 患者，中耳手术前后。这一地区将 包括1)调查MLD性能的时间进程， 在手术前，手术后不久，然后定期测量 间隔四年，以便检查是否有可能 从声音剥夺中恢复过来。2)潜力的调查 双耳听力差的原因(除剥夺外) 中耳手术后，包括声学交叉，和 音程间相位不匹配。3)调查潜在的 更好地预测中耳手术后的双耳听力。4) 对不对称效应的研究，其中 传导性不对称性似乎比模拟的要大得多。 听力正常受试者的不对称性。5)调查一名 第二个不对称效应，其中MLD的表现不对称 出现在“坏”耳上的信号似乎更差。 而不是提供给“好”的耳朵的信号。对这些问题的调查 这些问题将有助于我们对双耳传导听力的理解 听力损失，双耳听力障碍的潜在恢复 停止声音剥夺后，有可能变得更好 预测术后双耳优势。MLD将是 使用标准耳机和插入式耳机进行测量，以便 评估交叉的可能重要性，并使用一系列 模拟耳间时间延迟，以抵消可能的延迟 由中耳病理或外科假体引起。两个人 耳朵将在相等的SL和相等的SPL下受到刺激。 该项目的第二个主要领域将调查其影响 儿童双耳听力不同于中耳炎。这项研究 将对早期听觉剥夺的假设进行调查 童年可能导致双耳听力不佳，由 MLD。其中一项实验将检测5岁儿童的MLD， 7岁和9岁，听力正常，但有OM病史 年龄在5岁之前。第二个实验将检验MLD 在4-5岁的受试者中纵向(超过四年)仍然 在进入学习时体验OM。第二项研究将 提供中更改的时间进程的详细说明 在听力剥夺期间和之后的双耳听力， 将直接与成人纵向数据相比较(见 上图)。对耳间时间和音量提示的反应将是 独立测量。疾病的不对称性因素 并对听力损失缓解后的时间进行评估。在……里面 这两个项目领域的心理物理方法将是三个- 替代强制选择测试，声音呈现结束 耳机。该项目的所有阶段都将包括年龄匹配 控制对象的结果将进一步加深我们对 正常双耳听力。数据将使用以下分析进行分析 差异和相关程序。

The long-term objectives of this project are a better understanding of the effect of conductive hearing loss on the binaural hearing of adults and children. The first aim of the present project will investigate factors that contribute to poor masking-level difference performance in adult conductive lesion patients, before and after middle ear surgery. This area will include 1) Investigation of the time-course of MLD performance, measuring before surgery, soon after surgery, and then at regular intervals over a four year period, in order to examine possible recovery from sound deprivation. 2) Investigation of potential causes of poor binaural hearing (besides deprivation) before and after middle ear surgery, including acoustic cross-over, and interear phase mismatch. 3) Investigation of the potential for better predicting binaural hearing after middle ear surgery. 4) Investigation of an asymmetry effect, where the effect of conductive asymmetry appears to be much greater than simulated asymmetries in normal-hearing subjects. 5) Investigation of a second asymmetry effect, where MLD performance in asymmetric cases appears to be poorer for signals presented to the "bad" ear than signals presented to the "good" ear. Investigation of these issues will aid our understanding of binaural hearing in conductive hearing loss, potential recovery from deficits in binaural hearing after cessation of sound deprivation, and potential for better predicting post-surgical binaural advantage. The MLD will be measured using both standard and insert earphones, in order to assess possible importance of crossover, and using a range of simulated inter-ear time delays, in order to offset possible delays caused by middle ear pathology or surgical prosthesis. The two ears will be stimulated at both equal SL and equal SPL. The second major area of the project will investigate the effect of otitis media no the binaural hearing of children. This research will investigate the hypothesis that auditory deprivation in early childhood may result in poor binaural hearing, as measured by the MLD. One experiment will examine the MLD in children aged 5, 7, and 9 years old, who have normal hearing but histories of OM before age 5 years. A second experiment will examine the MLD longitudinally (over four years) in 4-5 year old subjects still experiencing OM on entry into study. This second study will provide a detailed description of the time course of changes in binaural hearing during and following auditory deprivation, which will be directly comparable to the adult longitudinal data (see above). Response to cues of interaural time and level will be measured independently. The factors of asymmetry of disease and time after resolution of hearing loss will be evaluated. In both project areas the psychophysical method will be three- alternative forced-choice testing with sound presentation over earphones. All phases of the project will include age-matched control subjects whose results will further our understanding of normal binaural hearing. Data will be analyzed using analysis of variance and correlation procedures.