Sign advantage: Both children and adults' spatial expressions in sign are more informative than those in speech and gestures combined

• Published in: Journal of child language Vol. 51; no. 4; p. 876
• Main Authors: Karadöller, Dilay Z, Sümer, Beyza, Ünal, Ercenur, Özyürek, Aslı
• Format: Journal Article
• Language: English
• Published: England 01.07.2024
• Subjects: Adult; Child; Deafness - psychology; Female; Gestures; Humans; Male; Sign Language; Speech; Turkey; Turkey; sign language; development; co-speech gesture; spatial language; iconicity
• ISSN: 1469-7602
• DOI: 10.1017/S0305000922000642

Expressing Left-Right relations is challenging for speaking-children. Yet, this challenge was absent for signing-children, possibly due to iconicity in the visual-spatial modality of expression. We investigate whether there is also a modality advantage when speaking-children's co-speech gestures are considered. Eight-year-old child and adult hearing monolingual Turkish speakers and deaf signers of Turkish-Sign-Language described pictures of objects in various spatial relations. Descriptions were coded for informativeness in speech, sign, and speech-gesture combinations for encoding Left-Right relations. The use of co-speech gestures increased the informativeness of speakers' spatial expressions compared to speech-only. This pattern was more prominent for children than adults. However, signing-adults and children were more informative than child and adult speakers even when co-speech gestures were considered. Thus, both speaking- and signing-children benefit from iconic expressions in visual modality. Finally, in each modality, children were less informative than adults, pointing to the challenge of this spatial domain in development.