Learning words by hand: Gesture's role in predicting vocabulary development.

Children vary widely in how quickly their vocabularies grow. Can looking at early gesture use in children and parents help us predict this variability? We videotaped 53 English-speaking parent-child dyads in their homes during their daily activities for 90-minutes every four months between child age 14 and 34 months. At 42 months, children were given the Peabody Picture Vocabulary Test (PPVT). We found that child gesture use at 14 months was a significant predictor of vocabulary size at 42 months, above and beyond the effects of parent and child word use at 14 months. Parent gesture use at 14 months was not directly related to vocabulary development, but did relate to child gesture use at 14 months which, in turn, predicted child vocabulary. These relations hold even when background factors such as socio-economic status are controlled. The findings underscore the importance of examining early gesture when predicting child vocabulary development.