Susceptibility to and Release from Masking in Infancy and Childhood

描述(申请人提供)：婴儿和儿童比成人更容易受到背景竞争声音的干扰。听觉掩蔽的这些发育影响对于听力正常的儿童来说可能是实质性的，但对于听力障碍的儿童来说更加明显。尽管婴儿必须在存在竞争声音的情况下学习言语和语言，但我们对影响儿童在噪音中听力的因素了解有限，很少有研究解决婴儿和听力障碍儿童面临的具体挑战。该项目的长期目标是确定和解释在包含多种声源的复杂声学环境中导致听力发展的因素。拟议的实验将表征在存在竞争背景声音的情况下听到目标音调或语音的能力的发育影响，并将确定声学线索组合，以改善听力正常和听力受损的婴儿和儿童在噪音中的听力。目标1将描绘远程频率掩蔽从婴儿期到青春期的发展过程。拟议中的研究将检验这一假设，即对来自远程频率背景声音的干扰的敏感性随着年龄的增长而降低。目标2将调查婴儿和儿童在存在相互竞争的背景声音的情况下，从提供健壮和/或冗余的听觉分组线索中受益的程度。这些研究将检验这样一个假设，即当声音来源分离线索相对稀少时，婴儿和儿童从这些线索中获得的好处比成年人少。目标3将为听力受损的婴儿和儿童确定在存在竞争背景声音的情况下改善听力的声学提示。这项工作将验证听力障碍干扰听觉处理能力的假设，该能力与背景声音中目标的分离和选择有关。为所有三个目标提出的实验依赖于严格的行为方法，使用特征良好的多音调和噪声刺激，以及在存在竞争噪声或语音掩蔽物的情况下进行语音感知测试。拟议的研究结果将提供亟需的标准化数据，并有望有助于形成复杂听觉感知的儿科测量方法。这些数据也有可能导致改进策略，以优化听力障碍婴儿和儿童的听觉信息传递。 公共卫生相关性：拟议的研究结果将提供关于限制婴儿和儿童在嘈杂环境中听到目标声音的能力的因素以及听力障碍儿童面临的具体挑战的宝贵信息。这些信息与公共卫生有关，因为它将为临床听力测量提供急需的标准化数据，以评估复杂的听觉技能。这些数据也有可能导致开发新的干预策略，以改善为听力受损的婴儿和儿童提供的听觉信息。

DESCRIPTION (provided by applicant): Infants and children are more vulnerable to interference from competing backgrounds sounds than adults. These development effects in auditory masking can be substantial for children with normal hearing sensitivity, but are more pronounced for children with hearing impairment. Despite the fact that infants must learn about speech and language in the presence of competing sounds, we have a limited understanding of the factors that influence children's hearing in noise, and few studies have addressed the specific challenges faced by infants and children with hearing impairment. The long-term aim of this project is to identify and explain the factors responsible for the development of hearing in complex acoustic environments that contain multiple sources of sound. The proposed experiments will characterize developmental effects in the ability to hear target tones or speech in the presence of competing background sounds and will identify acoustic-cue combinations that improve hearing in noise for both normal-hearing and hearing-impaired infants and children. Aim 1 will delineate the time course of development for remote-frequency masking from infancy to adolescence. The proposed studies will test the hypothesis that susceptibility to interference from remote-frequency background sounds decreases with increasing age. Aim 2 will investigate the extent to which infants and children benefit from the provision of robust and/or redundant auditory grouping cues in the presence of competing background sounds. These studies will test the hypothesis that infants and children benefit less than adults from sound source segregation cues when those cues are relatively sparse. Aim 3 will identify acoustic cues that improve hearing in the presence of competing background sounds for infants and children with hearing impairment. This work will test the hypothesis that hearing impairment interferes with auditory processing abilities related to the segregation and selection of target from background sounds. Experiments proposed for all three aims rely on rigorous behavioral methods using well-characterized multi-tonal and noise stimuli as well as speech perception testing in the presence of competing noise or speech maskers. The results of the proposed studies will provide much needed normative data and are expected to contribute to the formation of pediatric measures of complex auditory perception. There is also the potential these data will lead to improved strategies to optimize the delivery of auditory information for infants and children with hearing impairment. PUBLIC HEALTH RELEVANCE: The results of the proposed studies will provide valuable information about the factors that limit infants' and children's abilities to hear target sounds in noisy environments and the specific challenges faced by children with hearing impairment. This information is relevant to public health because it will provide much-needed normative data for clinical hearing measures designed to assess complex auditory skills. There is also the potential these data could lead to the development of new intervention strategies to improve the provision of auditory information for infants and children with hearing impairment.