Backchannels as multimodal displays of joint understanding in signed language interaction: A cross-linguistic analysis of Norwegian Sign Language and French Belgian Sign Language conversations

This study investigates how deaf signers from two historically unrelated signed languages (SLs), Norwegian SL and French Belgian SL (LSFB), signal understanding through backchannels (BCs). BCs include short vocal (e.g., mm mm) and visual cues (e.g., head nodding, facial expressions) or a combination of both. While most research on BCs examines spoken languages, little is known comparatively about BCs in signed discourse. The current study addresses this gap by analyzing BC production in the discourse of 42 deaf signers of Norwegian SL and LSFB, offering key cross-linguistic insights into BC forms and types in two under-documented SLs. ELAN was used to identify 4,325 tokens of BCs (e.g., manual/nonmanual; the bodily articulators used) observed in 4 hours of face-to-face dyadic conversational data from the Norwegian SL and LSFB Corpora. Annotations were then subjected to multivariate statistical analysis in R. Findings reveal similarities and some differences across both SLs. BCs were primarily performed nonmanually, showing limited variation in the range of articulators used. Head nods stood out as the most robust form in both SLs. However, inter-individual variation in BC styles was also observed. These differences may be linked to contextual factors and signer personalities, independent of SL. Ultimately, this work emphasizes the importance of investigating interactional phenomena at the heart of language such as BC from a multimodal and cross-linguistic perspective.