Nouns and verbs in a self-styled gesture system: what's in a name?

A distinction between nouns and verbs is not only universal to all natural languages but it also appears to be central to the structure and function of language. The purpose of this study was to determine whether a deaf child who was not exposed to a usable model of a conventional language would nevertheless incorporate into his self-styled communication system this apparently essential distinction. We found that the child initially maintained a distinction between nouns and verbs by using one set of gestures as nouns and a separate set as verbs. At age 3:3, the child began to use some of his gestures in both grammatical roles; however, he distinguished the two uses by altering the form of the gesture (akin to morphological marking) and its position in a gesture sentence (akin to syntactic marking). Such systematic marking was not found in the spontaneous gestures produced by the child's hearing mother who used gesture as an adjunct to speech rather than as a primary communication system. A distinction between nouns and verbs thus appears to be sufficiently fundamental to human language that it can be reinvented by a child who does not have access to a culturally shared linguistic system.