Development and plasticity in normal and impaired ears

描述（由申请人提供）：本项目的长期目标是了解正常儿童和有渗出性中耳炎（OME）病史的儿童的听觉发育/可塑性。目标1和2分别涉及双耳时间和频谱处理的发展。目标3关注有慢性OME病史的儿童言语感知的发展和可塑性。目的1调查发展方面的一个新确定的重要双耳时间的能力，利用有利的SIN比掩蔽噪声包络最小值。我们将测试两个特定的假设：1）儿童的这种能力表现出持久的改善，可以用双耳时间窗的发展来表征; 2）这种能力可以解释成人和儿童掩蔽水平差异（MLD）中迄今无法解释的个体差异。第二个具体目标研究解决和利用双耳间时间差（ITD）的跨频率差的能力。目标是发展有效的方法来表征这种能力及其发展，并验证这种能力在儿童中具有持久发展的假设。我们还将测试的假设，跨频率的ITD差异的敏感性取决于是否伴随刺激变量有利于合成或分析模式的处理。在目标3中，我们将使用言语感知方法来研究OME发生的异常/不稳定阈值和频谱形状条件下的听觉发育和可塑性。这些研究将检验这样的假设，即频谱加权和将来自不同频率区域的联合收割机信息组合的能力在有OME病史的儿童中是异常的，这可能是由于语音信息的频谱形状在听觉发育期间是异常的并且在长时间内是不稳定的。心理声学研究将使用标准的自适应测试技术，语音研究将确定在安静或语音形状掩蔽噪声中呈现的句子的正确率。该项目的所有阶段都将包括年龄匹配的控制监听器。将使用方差分析和相关程序分析数据。

DESCRIPTION (provided by applicant): The long-term aim of this project is an understanding of auditory development/plasticity in normal children and in children having a history of otitis media with effusion (OME). Aims 1 and 2 concern the development of binaural temporal and spectral processing, respectively. Aim 3 concerns development and plasticity in the perception of speech for children who have histories of chronic OME. Aim 1 investigates developmental aspects of a newly identified important binaural temporal ability to take advantage of the favorable SIN ratios available in masking noise envelope minima. We will test two specific hypotheses: 1) this ability in children shows a protracted improvement that can be characterized in terms of the development of the binaural temporal window; 2) this ability can account for hitherto unexplained individual differences in the masking level difference (MLD) in adults and in children. The second specific aim investigates the ability to resolve and utilize across-frequency differences in binaural interaural time differences (ITDs). Goals are to develop efficient methods to characterize this ability and its development, and to test the hypothesis that this ability has a protracted development in children. We will also test the hypothesis that sensitivity to across-frequency differences in ITDs depends upon whether concomitant stimulus variables favor a synthetic or analytic mode of processing. In Aim 3 we will use a speech perception approach to investigate auditory development and plasticity under conditions of abnormal/unstable thresholds and spectral shape that occur with OME. These studies will test the hypothesis that spectral weighting and the ability to combine information from different frequency regions is abnormal in children with OME history, perhaps due to the fact that the spectral shape of speech information is abnormal and unstable for prolonged periods of time during auditory development. Psychoacoustic studies will use standard, adaptive testing techniques, and speech studies will determine percent correct for sentences presented either in quiet or in speech-shaped masking noise. All phases of the project will include age-matched control listeners. Data will be analyzed using analysis of variance and correlation procedures.