Department of Medical Social Sciences, Northwestern University, Chicago, IL, United States of America; Department of Psychology, Northwestern University, Evanston, IL, United States of America.
Department of Linguistics, University of Chicago, Chicago, IL, United States of America.
Cognition. 2021 Oct;215:104845. doi: 10.1016/j.cognition.2021.104845. Epub 2021 Jul 14.
The link between language and cognition is unique to our species and emerges early in infancy. Here, we provide the first evidence that this precocious language-cognition link is not limited to spoken language, but is instead sufficiently broad to include sign language, a language presented in the visual modality. Four- to six-month-old hearing infants, never before exposed to sign language, were familiarized to a series of category exemplars, each presented by a woman who either signed in American Sign Language (ASL) while pointing and gazing toward the objects, or pointed and gazed without language (control). At test, infants viewed two images: one, a new member of the now-familiar category; and the other, a member of an entirely new category. Four-month-old infants who observed ASL distinguished between the two test objects, indicating that they had successfully formed the object category; they were as successful as age-mates who listened to their native (spoken) language. Moreover, it was specifically the linguistic elements of sign language that drove this facilitative effect: infants in the control condition, who observed the woman only pointing and gazing failed to form object categories. Finally, the cognitive advantages of observing ASL quickly narrow in hearing infants: by 5- to 6-months, watching ASL no longer supports categorization, although listening to their native spoken language continues to do so. Together, these findings illuminate the breadth of infants' early link between language and cognition and offer insight into how it unfolds.
语言和认知之间的联系是人类所独有的，并且在婴儿期早期就出现了。在这里，我们提供了第一个证据，证明这种早熟的语言认知联系不仅限于口语，而是足够广泛，包括手语，这是一种以视觉方式呈现的语言。4 到 6 个月大的听力婴儿，以前从未接触过手语，他们熟悉一系列类别示例，每个示例都是由一名女性通过美国手语 (ASL) 进行展示，同时指向和注视物体，或者在没有语言的情况下指向和注视（对照）。在测试中，婴儿观看了两张图片：一张是现在熟悉的类别中的新成员；另一张是全新类别的成员。观察 ASL 的 4 个月大的婴儿能够区分这两个测试对象，表明他们已经成功地形成了物体类别；他们和听母语（口语）的同龄婴儿一样成功。此外，正是手语的语言元素推动了这种促进作用：只观察女性指向和注视的对照组婴儿未能形成物体类别。最后，观察 ASL 对听力婴儿认知优势的影响迅速缩小：到 5 到 6 个月大时，观看 ASL 不再支持分类，尽管听母语继续支持。总之，这些发现阐明了婴儿早期语言和认知之间联系的广度，并提供了对其发展方式的深入了解。
