ROLES OF EARLY EXPERIENCE IN DEVELOPMENT OF HEARING

我们建议调查早期听力损失对双耳听力的影响， 处理和高频阈值。我们的部门吸引了 先天性耳道闭锁这些受试者有畸形的外部和 内耳通常是正常的。手术成功 将大的传导性听力损失矫正到正常或接近正常的限度。 一组实验调查了听力损失对 双耳处理的不同方面。一组测试探头 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 差异阈值、掩蔽水平差异和自由场定位。 我们假设，这些能力中有许多（但不是全部）会迅速出现 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。 第二个单独的实验研究了 环境噪音。我们建议使用受保护的听力阈值 和正常的耳朵来衡量相对贡献，遗传和 环境因素对长期听力损失的影响。 来自一组独特的听力受损听众的数据将用于 评估异常听觉体验的多种影响。这些受试者 可以为研究中的重要问题提供有意义的答案 听觉系统的发展：特别是，恢复的时间过程 改变的输入和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.