Sensitivity to spectral cues in infant speech perception

描述（由申请人提供）：拟议的研究将检查婴儿对言语感知中多种频谱线索的敏感性。语音是一个复杂的信号，每个辅音和元音都有许多声学线索。通过经验，听众学会利用多种线索之间的相关性，使感知更加有效和强大。成年人通过使用频谱局部（例如共振峰转换）以及分布（例如总频谱形状或倾斜）的线索来区分语音声音来显示这种知识。虽然先前的研究已经证明婴儿有能力区分许多语音，但他们如何区分这些声音尚不清楚。婴儿对单个线索的敏感性，他们对每个线索的相对重要性，以及他们何时学会利用线索之间的相关性，都仍然知之甚少。我们提出了四个实验来解决这些问题。本项目的第一个目的是调查光谱线索的敏感性。为了解决这个问题，前两个实验将检查语音感知时，两个线索之间的自然协方差被违反或维持。后两个实验将测试对个体线索变化的敏感性。第二个目标是评估整个生命周期的相对线索显著性。从第一个实验的结果将进行比较，从正常的听力和听力受损的老年成年听众谁完成了类似的任务（亚历山大和Kluender，在出版物中;在准备），以评估听力体验和听力健康的差异影响感知相同的语音刺激。我们假设，6至7个月大和11至12个月大的婴儿都将表现出对语音感知中的两种频谱线索的感知敏感性，其中11至12个月大的婴儿表现出最大的敏感性。我们还假设，年龄较小的婴儿可能是相对更受影响的频谱全球（如倾斜）线索比年龄较大的婴儿。我们的长期目标是更好地了解听力正常和受损婴儿的言语感知发展。这些结果将有助于改善听力损失婴儿的治疗方法，并为助听器和人工耳蜗植入等设备的使用提供信息。公共卫生声明：这项拟议中的研究将揭示婴儿用来区分语音的声学信息，以及成年人是否会以不同的方式使用这些信息。了解婴儿听什么将有助于促进听力受损儿童言语知觉的发展。这项研究还将调查婴儿何时学会利用自然语言中线索之间的统计差异。

DESCRIPTION (provided by applicant): The proposed research will examine infants' sensitivity to multiple spectral cues in speech perception. Speech is a complex signal, with numerous acoustic cues for every consonant and vowel. Through experience, listeners learn to exploit correlations between multiple cues, making perception more efficient and robust. Adults display this knowledge through their use of cues that are spectrally local (e.g. formant transitions) as well as distributed (e.g. gross spectral shape, or tilt) to distinguish speech sounds. Although prior research has demonstrated infants' ability to distinguish many speech sounds, how they distinguish these sounds is unclear. Infants' sensitivity to individual cues, the relative importance they assign to each cue, and when they learn to exploit correlations between cues all remain poorly understood. We propose four experiments to address these questions. The first aim of this project is to investigate sensitivity to spectral cues. To address this issue, the first two experiments will examine speech perception when the natural covariance between two cues is violated or maintained. The latter two experiments will test sensitivity to changes in individual cues. The second aim is to assess relative cue salience across the lifespan. Results from the first experiment will be compared to existing data from normal-hearing and hearing-impaired elderly adult listeners who completed a similar task (Alexander & Kluender, in press; in preparation) to assess differential effects of listening experience and hearing health on perception of the same speech stimuli. We hypothesize that both 6-to-7-month-old and 11-to-12-month-old-infants will exhibit perceptual sensitivity to both spectral cues in speech perception, with 11-to-12-month-olds displaying the greatest sensitivity. We also hypothesize that younger infants may be relatively more influenced by spectrally global (e.g. tilt) cues than older infants. Our long-term objective is to better understand development of speech perception in infants with normal and compromised hearing. These results will help refine treatment methods for infants with hearing loss, and inform the use of devices such as hearing aids and cochlear implants. Public health statement: The proposed research will reveal the acoustic information infants use to distinguish speech sounds, and whether this information is used differently by adults. Knowing what infants listen for will benefit efforts to facilitate development of speech perception in children with compromised hearing. This research will also investigate when infants learn to exploit statistical regularities between cues in natural speech.