BINAURAL HEARING BEFORE AND AFTER MIDDLE EAR SURGERY

该项目的长期目标是了解 传导性听力损失对双耳听力的影响， 中耳手术对双耳听力的影响， 预测中耳手术是否可以用来恢复双耳 听觉障碍患者的听力。 它经常被认为是 承认中耳手术将改善双耳听力：目前 该项目将直接测试这一假设。 的具体目标 目前的研究是评估镫骨切除术的效果， 鼓室成形术对双耳听力的影响，检查1）对称性 2）听力损失的严重程度，3）病因 听力损失，4）听力耳蜗组件的影响 损耗（通过频率选择性和骨传导测量 阈值），以及5）表现背后的特定类型的线索 （耳间时间与耳间振幅差异）。 所有的刺激都将是 通过耳机呈现，以便精确控制提示的类型 available. 双耳测试将包括通过以下线索进行偏侧化： 耳间时间差和噪声检测（掩蔽水平 通过耳间时间差或耳间时间差 振幅差分 频率选择性的单声道测试（陷波 噪声方法）将被用作耳蜗功能的测量。 测试将 在一个经过声音处理的房间里进行，三个间隔，三个 在所有任务中将采用另一种被迫选择的适应性程序。 受试者将包括正常听力对照组（n=12）， 患有耳硬化症且听力对称（n=12），患者有 耳硬化伴不对称听力（n=12）， 对称听力（n=12）和中耳炎患者， 听力不对称（n=12）。 测试将在四点之前进行 中耳手术后的几个月。 将使用以下分析来分析数据： 方差和相关程序。

The long-term objectives of this project are an understanding of the impact of conductive hearing losses on binaural hearing, an understanding of the effects of middle ear surgery on binaural hearing, and a means of predicting whether middle ear surgery can be used to restore binaural hearing in a given conductively impaired patient. It is often taken for granted that middle ear surgery will improve binaural hearing: the present project will test this assumption directly. The specific aims of the present investigation are to assess the effects of stapedectomy and tympanoplasty on binaural hearing, examining the factors of 1) the symmetry of the hearing loss, 2) the severity of the hearing loss, 3) the etiology of the hearing loss, 4) the effect of a cochlear component of the hearing loss (as measured by frequency selectivity and by bone conduction threshold), and 5) the specific kind of cue underlying performance (interaural time vs interaural amplitude disparity). All stimuli will be presented over earphones in order to control precisely the type of cue available. The binaural tests will include lateralization by the cue of interaural time difference, and detection in noise (Masking Level Difference) by the cues of either interaural time difference or interaural amplitude difference. A monaural test of frequency selectivity (notched noise method) will be used as a measure of cochlear function. Testing will be performed in a sound-treated room, and a three interval, three alternative, forced-choice adaptive procedure will be used in all tasks. Subjects will include a normal-hearing control group (n=12), patients having otosclerosis with symmetrical hearing (n=12), patients having otosclerosis with asymmetrical hearing (n=12), patients otitis media with symmetrical hearing (n=12), and patients having otitis media with asymmetrical hearing (n=12). Testing will be performed before and four months after middle ear surgery. Data will be analyzed using analysis of variance and correlation procedures.