The parallel development of the form and meaning of two-handed gestures and linguistic information packaging within a clause in narrative

We examined how two-handed gestures and speech with equivalent contents that are used in narrative develop during childhood. The participants were 40 native speakers of English consisting of four different age groups: 3-, 5-, 9-year-olds, and adults. A set of 10 video clips depicting motion events were used to elicit speech and gesture. There are two findings. First, two types of two-handed gestures showed different developmental changes: those with a single-handed stroke with a simultaneous hold increased with age, while those with a two handed-stroke decreased with age. Second, representational gesture and speech developed in parallel at the discourse level. More specifically, the ways in which information is packaged in a gesture and in a clause are similar for a given age group; that is, gesture and speech develop hand-in-hand