Motion events in French Sign Language and spoken French acquisition

International audienceLinguistic research reveals the need to consider linguistic diversity to better understand the impact of universal and language-specific determinants on individuals’ spatial representations and on spatial language acquisition. Our study examines motion expression in French Sign Language (LSF) with particular attention to the fundamental role of iconicity in defining specific properties of sign languages (SLs) and their implications for acquisition within an approach that is both typological (Slobin 2004) and semiological (Cuxac 1999). We compare productions in LSF by Deaf children of Deaf parents, aged 4-5 and 8-9, and Deaf adults (6 in each age group, data annotated with ELAN) and in spoken French by same-aged hearing French speakers (24 per age, data annotated with CLAN). All participants described 26 video clips showing agents carrying out motion in varied manners (e.g. walking, running, swimming) along three paths (up, down, across). Results show that motion expression is more specific and denser (Path and Manner) in LSF than in French (mostly Path) at all ages. This information is encoded either simultaneously within the same structure or in successive constructions describing the same event from different perspectives (internal vs. external). Findings also show the impact of event types on signers’ uses of different highly iconic structures (vs. lexical signs) that invite them to focus on different semantic components of motion. Although semantic density did not increase with age in LSF (contrary to French), results show an increase in response specificity, indicating gradually more complete and precise motion descriptions. Furthermore, developmental changes occurred with respect to the types of structures used.To conclude, although we observe developmental progressions in both languages, patterns differ significantly between LSF and French at all ages. This suggests that modality impacts acquisition, inviting us to compare these results with coverbal gestures (Özyürek, Furman & Goldin-Meadow 2014)