Development of Frequency Resolution in Infancy

婴儿期频率分辨率的发展

• 批准号: 8677863
• 负责人: Lynne A. Werner
• 金额: $ 35.66万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-06-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8677863
• 关键词: Acoustics; Address; Adult; Affect; Age; Age-Months; Attention; Auditory; Auditory Evoked Potentials; Auditory area; Auditory system; Brain Stem; Child; Complex; Development; Dimensions; Discrimination; Elderly; Environment; Failure; Frequencies; Goals; Hearing; Human; Infant; Intervention; Laboratories; Language; Language Disorders; Learning; Masks; Modeling; Nature; Nervous system structure; Neural Pathways; Outcome; Output; Pathway interactions; Perception; Performance; Process; Property; Psychoacoustics; Psychophysics; Research; Resolution; Shapes; Side; Signal Transduction; Source; Speech; Stream; Television; Testing; Time; Work; age related; auditory pathway; base; effective intervention; experience; infancy; neurodevelopment; neuromechanism; perceptual organization; programs; relating to nervous system; research study; selective attention; sound

DESCRIPTION (provided by applicant): The long-term goal of this program of research is to describe and to understand changes in hearing that occur during human infancy. Recent work has focused on infants' ability to process one sound in the presence of competing sounds. The results show that the sound properties that influence this ability differ between adults and 7-9-month-old infants, suggesting that the mechanisms underlying listening in complex environments are also different. A new synthesis of work describing the development of auditory neural pathways leads to new hypotheses concerning the nature of such age-related changes in hearing. Specifically, it appears that the source of input to auditory cortex shifts around 6 months of age. If that is the case, then infants younger than 6 months are predicted to respond in a qualitatively different way from infants older than 6 months to situations in which selective processing of one sound in the presence of another is required. The goal of the proposed work is to test that general hypothesis. The proposed experiments address three specific aims. The first aim is to determine whether 3- and 7-month-old infants are able to extract some of the important sound attributes- pitch, spectral shape, and modulation-that are used by adults to separate competing sounds into different auditory streams. Infants' ability to discriminate vowels and musical notes that differ along these dimensions will be tested. It is hypothesized that infants will be able to discriminate sounds along all three dimensions. The second specific aim is to determine whether 3- and 7-month-old infants are able to separate two concurrent streams of vowels or musical notes. The concurrent streams will differ along the dimensions of pitch, spectral shape and modulation, according to the results of the experiments addressing the first specific aim. Infants' ability to discriminate a change in a vowel or musical note in one stream in the presence of an unchanging stream will be tested. It is hypothesized that both 3-month-olds and 7-month-olds will be able to perform this task when the streams differ in spectral shape and perhaps modulation, but not when they differ in pitch. The third specific aim is to determine whether 3- and 7-month-old infants are able to selectively process a change in a vowel or musical note in only one of two streams when the same change can occur in the competing stream. Infants' ability to discriminate a change in a vowel or musical note in a specific stream will be tested, but under conditions in which the same change sometimes occurs in the competing stream. It is hypothesized that 7-month-olds, but not 3-month-olds will be able to perform this task. The results of these experiments will have implications for current models of auditory neural development and for models of perceptual organization in mature listeners.

描述（由申请人提供）：本研究计划的长期目标是描述和理解人类婴儿期发生的听力变化。最近的工作集中在婴儿在竞争声音存在的情况下处理一种声音的能力。结果表明，影响这种能力的声音特性在成人和7-9个月大的婴儿之间存在差异，这表明在复杂环境中倾听的机制也不同。一个新的合成工作描述的听觉神经通路的发展导致新的假设有关的性质，这种年龄相关的听力变化。具体来说，似乎听觉皮层的输入源在6个月左右发生了变化。如果是这样的话，那么小于6个月的婴儿预计会以与6个月以上的婴儿不同的方式对需要在一种声音存在的情况下选择性处理另一种声音的情况做出反应。拟议工作的目标是检验这一一般假设。拟议的实验涉及三个具体目标。第一个目标是确定3个月和7个月大的婴儿是否能够提取一些重要的声音属性-音高，频谱形状和调制-成人使用这些属性将竞争声音分成不同的听觉流。婴儿辨别元音和音符的能力将被测试，这些元音和音符在沿着这些维度上不同。据推测，婴儿将能够区分声音沿着所有三个方面。第二个具体目标是确定3个月和7个月大的婴儿是否能够分离两个并发的元音或音符流。根据解决第一特定目标的实验结果，并行流将沿着音调、频谱形状和调制的维度沿着不同。婴儿辨别元音或音符在一个音流中变化的能力 将测试不变流的存在。据推测，3个月大和7个月大的婴儿将能够执行这项任务时，流不同的频谱形状，也许调制，但不是当他们不同的音高。第三个具体目标是确定3个月和7个月大的婴儿是否能够选择性地处理两个流中仅一个流中的元音或音符的变化，而相同的变化可以发生在竞争流中。测试婴儿辨别特定音流中元音或音符变化的能力，但条件是在竞争音流中有时发生相同变化。据推测，7个月大的婴儿，而不是3个月大的婴儿将能够执行这项任务。这些实验的结果将对当前的听觉神经发育模型和成熟听众的感知组织模型产生影响。