ROLES OF EARLY EXPERIENCE IN DEVELOPMENT OF HEARING

我们建议研究早期听力损失对双耳的影响。 处理阈值和高频阈值。我们部门吸引了很多科目 患有先天性耳道闭锁。这些受试者有畸形的外部和 中耳，而内耳通常是正常的。手术成功 将较大的传导性听力损失纠正到正常或接近正常极限。 一组实验调查了听力损失对 双耳处理的不同方面。一系列测试探头 对耳间水平、时间和相位差异作出反应的能力。 这些任务包括双耳响度、平衡、耳间时间 差异限制、掩蔽级别差异和自由场局部化。 我们假设，这些能力中的许多，但不是全部，都会迅速出现。 在矫正手术后，显示早期传导性听力损失 不一定会导致永久性损伤。 第二个也是单独的实验调查了 环境噪音。我们建议使用受保护的听力阈值 和正常的耳朵来测量遗传和 环境因素可能会对长期听力损失产生影响。 来自一组独特的听障听众的数据将被用来 评估异常听觉体验的多重影响。这些科目 可以为研究中的重要问题提供有意义的答案 听觉系统发育：尤其是恢复的时间进程 改变的投入以及遗传和环境影响的相互作用。

We propose to investigate effects of early hearing loss on binaural processing and high-frequency thresholds. Our Department attracts subjects with congenital aural atresia. These subjects have a malformed external and middle ear while the inner ear is usually normal. Successful surgery corrects large conductive hearing losses to normal or near normal limits. One set of experiments investigates the effects of hearing loss on different aspects of binaural processing. A battery of tests probes abilities to respond to interaural level, temporal, and phase differences. These tasks include binaural loudness, balances, interaural temporal difference limens, masking level differences, and freefield localizations. We hypothesize that many, but not all, of these abilities emerge rapidly after corrective surgery, showing that early conductive hearing loss does not necessarily lead to permanent impairment. A second and separate experiment investigates the cumulative effect of environmental noise. We propose to use hearing thresholds from protected and normal ears to measure relative contributions that genetic and environmental factors may have on long-term hearing loss. Data from a unique group of hearing-impaired listeners will be used to evaluate multiple effects of abnormal auditory experience. These subjects could yield significant answers to important questions in the study of auditory system development: particularly, the time course of recovery from altered inputs and the interaction of genetic and environmental influences.