Lecture: The role of communication in the development of sign language lexicons
The most learnable language would be one with an identical form for every word. But the interactive nature of languages means they are under constant pressure to use distinct forms for distinct meanings, so as to allow for successful communication. In this talk I apply this principle to sign language, exploring whether a notable feature of sign languages can be explained as a result of the need to keep signs for different meanings visually distinct.
To represent an object iconically with your hands, gesturers (people who do not have a sign language) overwhelmingly mime the *use* of the object, shaping their hands as though holding and manipulating it (‘handling’ strategy). In contrast, sign language users are much more likely to shape their hands as though their hand *is* the object (‘instrument’ strategy). I hypothesised that this difference is due to the handling strategy having a greater risk of homophony (one form for multiple meanings), leading signers to favour the instrument strategy in order to communicate effectively.
To test this, 491 participants were shown signs for a range of meanings, using one of the two strategies (handling or instrument), and asked what they thought the meaning was. This talk describes the results of this experiment, in particular comparing how semantically varied interpretations were, for handling and instrument signs. A narrow range of interpretations would suggest high communicative efficacy for that sign, and reduced risk of homophony in a sign language lexicon using that sign.
While the primary finding was no overall difference between strategies, some words individually had a significant difference, with one strategy eliciting a wider range of meanings than another. I discuss the implications of these differences, and finally compare some other explanations for the differences between signers' and gesturers' productions.