Intersensory Perceptual Narrowing in Human Infants

描述(申请人提供)：灵长类动物的两个主要交流渠道是脸部和声音。正常情况下，面部手势和伴随的发声提供了高度冗余的信息，因为它们总是在空间上处于同一位置，在时间上同步，并由动态可听和可视信息的重叠模式指定。成年人从发声面孔提供的多感觉冗余中受益，因为他们使用这些冗余将分开的听觉和视觉信息流整合成连贯的感知体验，并且因为冗余使发声面孔更容易检测、学习和记忆。尽管现有的证据表明，利用多感官冗余的能力在婴儿早期就出现了，但其产生的过程仍然知之甚少。因此，当前的项目调查了人类婴儿的面部-声音整合的发展，并探索了知觉狭窄在感觉间整合的发展中起关键作用的新想法。这一新颖的想法是基于PI和他的同事们最近的一项发现，即年龄较小的婴儿比年龄较大的婴儿能够整合更广泛的面孔和声音。我们已经发现，年幼的婴儿可以整合非本地人的面孔和发音(无论是猴子的面孔和他们的发音，还是外来的可视和可听语音)，但较大的婴儿不能。我们的发现是惊人的，因为它们是违反直觉的，与现有的感觉间发育理论所产生的预测相反。然而，它们与越来越多的关于语音、面部和音乐加工领域的缩小效应的文献是一致的，并表明缩小是一个泛感官的、领域通用的过程。因此，目前的项目将研究感觉间知觉狭窄(IPN)。本研究将以5个具体目标为指导，其目的是阐明：(1)时间感觉间同步性、结构加工、手势特征和语言一般过程在IPN中的作用；(2)通过测试不同类型的整合任务来测试IPN的一般性质；(3)经验在IPN中的作用；(4)单一感觉知觉过程对IPN的单独贡献；以及(5)IPN的敏感期是否受到多感觉冗余的影响。我们将使用感觉间匹配技术来检查面孔-声音整合，使用习惯化/测试法来调查面孔和声音的学习和辨别，并测量婴儿的视觉注意力以衡量反应能力。通过揭示婴儿期面孔-声音整合发展的知觉和经验依赖机制，本项目将提供对关键沟通技能的出现的洞察，这一技能对于感知、认知和社会层面的适应功能至关重要。这反过来将提供对各种发育障碍(例如自闭症)的病因学的洞察，并将促进开发针对此类疾病的更好的诊断工具，并有助于开发更好的干预方法来改善这些疾病。 与公共卫生相关：自闭症的特点是，患有这种发育障碍的儿童无法对作为社交交流来源的人的面孔和声音做出反应，自闭症一直在以每年10%至17%的惊人速度增长。由于自闭症和相关的沟通和学习障碍本质上是发育性的，越早诊断出来，就越能有效地改善和/或预防它们。目前的项目将调查婴儿对人和S的面孔和声音做出反应的一些关键感知技能的发展，作为与社会相关的交流信息的来源。因此，该项目不仅将深入了解这些疾病功能受损的可能原因，而且还将为设计诊断工具提供科学基础，使这些疾病能够比目前更早地被发现并最终得到预防。

DESCRIPTION (provided by applicant): The two primary channels of communication in primate species are the face and the voice. Normally, facial gestures and accompanying vocalizations provide highly redundant information because they are always spatially co-located, temporally synchronous, and specified by overlapping patterns of dynamic audible and visible information. Adults profit from the multisensory redundancy that vocalizing faces offer because they use the redundancy to integrate the separate auditory and visual streams of information into coherent perceptual experiences and because the redundancy makes it easier to detect, learn, and remember vocalizing faces. Although extant evidence indicates that the ability to take advantage of multisensory redundancy emerges early in infancy, the processes underlying its emergence are still poorly understood. Consequently, the current project investigates the development of face-voice integration in human infants and explores the novel idea that perceptual narrowing plays a critical role in the development of intersensory integration. This novel idea is based on a recent discovery by the PI & his colleagues that younger infants can integrate a broader range of faces and voices than do older infants. We have found that young infants can integrate nonnative faces and vocalizations (either monkey faces and their vocalizations or foreign visible and audible speech sounds) but that older infants do not. Our findings are striking because they are counterintuitive and contrary to predictions arising from extant theories of intersensory development. They are, however, consistent with a growing literature on narrowing effects in the speech, face, and music processing domains and suggest that narrowing is a pan-sensory, domain-general process. Consequently, the current project will investigate intersensory perceptual narrowing (IPN). It will be guided by 5 specific aims whose purpose will be to shed light on: (1) the role of temporal intersensory synchrony, configural processing, gestural features, and language-general processes in IPN, (2) the general nature of IPN by testing for it across different types of integration tasks, (3) the role of experience in IPN, (4) the separate contribution of unisensory perceptual processes to IPN, and (5) whether the sensitive period for IPN is affected by multisensory redundancy. We will use the intersensory matching technique to examine face-voice integration, the habituation/test method to investigate learning and discrimination of faces and voices, and measure infant visual attention to index responsiveness. By shedding light on the perceptual and experience-dependent mechanisms that underlie the development of face-voice integration in infancy, this project will provide insights into the emergence of a critical communicative skill that is essential to adaptive functioning at the perceptual, cognitive, and social levels. This, in turn, will provide insights into the etiology of various developmental disorders (e.g., autism) and will facilitate the development of better diagnostic tools for such disorders and help develop better intervention methods to ameliorate these disorders. PUBLIC HEALTH RELEVANCE: Autism, whose hallmark is the inability of children with this developmental disability to respond to the faces and voices of people as sources of social communication, has been growing at an alarming rate of 10-17 percent per year. Because autism and related communication and learning disorders are developmental in nature, the earlier they are diagnosed the more effectively they can be ameliorated and/or prevented. The current project will investigate the development of some critical perceptual skills that enable infants to respond to people<s faces and voices as sources of socially relevant communicative information. As a result, not only will this project provide insights into the possible reasons for impaired functioning in these disorders but also a scientific basis for the design of diagnostic tools that will permit the detection of these disorders much earlier than is currently possible and ultimately their prevention.