From gesture to Sign? An exploration of the effects of communicative pressure, interaction, and time on the process of conventionalisation

This study explored how non-signers exploit their gestural repertoire during a process of handshape conventionalisation. We examined how communicative context, interaction, and time affect the transition from iconically motivated representations to linguistically organised, generalised forms. One hundred non-signers undertook a silent gesture-elicitation task, describing pictures in one of four conditions: (A) in isolation; (B) with a passive recipient tasked with identifying the objects gestured; (C) with an interlocutor, sharing addressor/addressee roles; (D) with a confederate, sharing addressor/addressee roles, where the confederate restricted her handshapes to four. Analyses focused on whether participants used their hands productively (proportion of 'hand-as-object' responses), and whether they generalised handshapes to similarly shaped but different objects (handshape range). High communicative pressure and interaction (C, D) generated the highest proportion of hand-as-object representations. The condition lacking these, (A), generated the smallest handshape range. Results did not change over time. At this incipient stage, individuals exploit their gestural repertoire productively, intent on depicting object characteristics accurately. Communicative pressure and interaction spur this exploratory process. However, they do not yet generalise their handshapes, a development requiring a loosening of the iconic mapping between symbol and referent. This aspect of conventionalisation needs time and might be more likely to emerge in isolation.