How does sign language compare with gesture, on the one hand, and spoken language on the other? Sign was once viewed as nothing more than a system of pictorial gestures without linguistic structure. More recently, researchers have argued that sign is no different from spoken language, with all of the same linguistic structures. The pendulum is currently swinging back toward the view that sign is gestural, or at least has gestural components. The goal of this review is to elucidate the (...) relationships among sign language, gesture, and spoken language. We do so by taking a close look not only at how sign has been studied over the past 50 years, but also at how the spontaneous gestures that accompany speech have been studied. We conclude that signers gesture just as speakers do. Both produce imagistic gestures along with more categorical signs or words. Because at present it is difficult to tell where sign stops and gesture begins, we suggest that sign should not be compared with speech alone but should be compared with speech-plus-gesture. Although it might be easier (and, in some cases, preferable) to blur the distinction between sign and gesture, we argue that distinguishing between sign (or speech) and gesture is essential to predict certain types of learning and allows us to understand the conditions under which gesture takes on properties of sign, and speech takes on properties of gesture. We end by calling for new technology that may help us better calibrate the borders between sign and gesture. (shrink)

Is displacement possible without language? This question was addressed in a recent work by Liszkowski and colleagues . The authors carried out an experiment to demonstrate that 12-month-old prelinguistic infants can communicate about absent entities by using pointing gestures, while chimpanzees cannot. The main hypothesis of their study is that displacement does not depend on language but is, however, exclusively human and instead depends on species-specific social-cognitive human skills. Against this hypothesis, we will argue that a symbolic representation is needed (...) to intentionally communicate absence and that this symbolic representation is tied to language. Moreover, data on the expression of displacement in home-sign systems will be taken into consideration. In light of this data, and in opposition to Liszkowski et al.'s claim, this paper will argue that displacement gestures are not foundational to language. Instead, they predate and predict .. (shrink)

It is difficult to create spoken forms that can be understood on the spot. But the manual modality, in large part because of its iconic potential, allows us to construct forms that are immediately understood, thus requiring essentially no time to develop. This paper contrasts manual forms for actions produced over three time spans—by silent gesturers who are asked to invent gestures on the spot; by homesigners who have created gesture systems over their life spans; and by signers who have (...) learned a conventional sign language from other signers—and finds that properties of the predicate differ across these time spans. Silent gesturers use location to establish co-reference in the way established sign languages do, but they show little evidence of the segmentation sign languages display in motion forms for manner and path, and little evidence of the finger complexity sign languages display in handshapes in predicates representing events. Homesigners, in contrast, not only use location to establish co-reference but also display segmentation in their motion forms for manner and path and finger complexity in their object handshapes, although they have not yet decreased finger complexity to the levels found in sign languages in their handling handshapes. The manual modality thus allows us to watch language as it grows, offering insight into factors that may have shaped and may continue to shape human language. (shrink)