You may point, but do not touch: Impact of gesture-types and cognition on language in typical and atypical development

Abstract

We investigated whether two types of pointing hand features (index finger and open palm pointing) and three types of relation with the referent (manipulation, contact, no contact) similarly predict language in children with and without autism, and whether cognition mediates the longitudinal relationship between pointing and language development. Sixteen children with autism, thirteen children at high risk for autism, and eighteen typically developing children participated in an interactive gesture-elicitation task and were tested on standardized cognitive and expressive language batteries in a longitudinal design. Cognition was a significant and direct predictor of language skills in all groups. However, index finger pointing was a direct predictor of language in the autism group above and beyond cognition. In addition, index finger pointing total score and percentage of no contact pointing bids were key predictors of expressive language measured one year apart, once the effect of group, expressive language and cognition at Time 1 were controlled. Findings highlight the role of cognition in communicative development, but suggest a key role of index finder use in the longitudinal relationship between deictic gestures and language atypical development above and beyond cognition.