The visual modality serves ‘double duty’ for sign language learners: A commentary on Karadöller, Sümer, and Özyürek

Karadöller and colleagues describe how a multimodal perspective provides a more complete and comprehensive understanding of language acquisition. I provide additional support for this view by describing two aspects of early interactions that support language acquisition—pointing and joint attention—that typically occur within a multimodal setting, but are achieved primarily in a single modality by deaf children acquiring sign language. In both examples, I describe how the visual modality serves ‘double duty’ for sign language learners: pointing takes on both a gestural and linguistic function, while joint attention is shaped around alternating attention to perceive both linguistic and non-linguistic input visually. These examples highlight the need to include sign language acquisition in theoretical accounts of language acquisition, to gain a more complete understanding of the flexible and adaptive nature of early interactions that support language development.