The well-documented gesture-language relation in typical communicative development (TD) remains understudied in autism spectrum disorder (ASD). Research on early communication skills shows that gesture production is a strong predictor of language in TD, but little is known about the association between gestures and language in ASD. This review focuses on exploring this relation by addressing two topics: the reliability of gestures as predictor of language competences in ASD and the types of potential differences (quantitative, qualitative, or both) in the gesture-language trajectory in children on the autism spectrum compared to typically developing children. We find evidence that gesture production is indeed a reliable predictor of early communicative skills and that both quantitative and qualitative differences have been established in research in the development of verbal and non-verbal communication skills in ASD, with lower gesture rates at the quantitative level, and a trajectory that starts deviating from the TD trajectory only at some point after the first year of life.

Deictic pointing is among the most impaired gestures in children with autism. Research on typical development demonstrates that contact with the referent and handshape when pointing, are associated with different communicative intentions and developmental stages. Despite their importance, the morphological features of pointing remain largely unexplored in autism. The aim of the present study was to map out pointing production in autism with a focus on handshape and contact with the referent. Participants (age range = 1–6 years old) with ASD (n = 16), at high risk for autism (n = 13) and typically developing children (n = 18) interacted with their caregivers in a gesture elicitation task. Results showed that children with ASD produced fewer pointing gestures overall and fewer index finger pointing without contact with the referent compared to the typically developing children. Lay Summary Children with autism produce less gestures than typical children, and pointing gestures appear to be more affected than other gesture types. Whether children point using their index finger or the palm, and whether they touch or not the referent is crucial for understanding communicative intentions. This is the first study to document experimentally exactly how pointing gestures differ in autism in comparison to typical development. We found important qualitative differences in the communicative patterns of children with autism and at risk for autism, that may serve to identify potential new markers for early diagnosis. Autism Res 2021, 14: 984–996. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.

Background: Evidence shows that the relation with the referent (object manipulation, contact/no contact pointing) and the different hand features (index finger/open palm) when pointing indicate different levels of cognitive and linguistic attainment in typical development (TD). This evidences the close link between pointing, cognition and language in TD, but this relation is understudied in autism. Moreover, the longitudinal pathway these abilities follow remains unexplored and it is unclear what specific role (predictor or mediator) pointing and cognition have in both typical and atypical language development. Aims: The first aim was to investigate whether pointing hand features (index finger/open palm) and relation with the referent (manipulation, contact and no contact pointing) similarly predict language in children with and without autism. The second aim was to explore whether cognition mediates the longitudinal relationship between pointing and language development. Methods & Procedures: Sixteen children with autism, 13 children at high risk (HR) for autism and 18 TD children participated in an interactive gestureelicitation task and were tested on standardised cognitive and expressive language batteries in a longitudinal design. A two-step analysis consisted of a stepwise linear regression and mediation analyses. First, the linear regression identified which hand features and types of relation with the referent predicted expressive language in all groups. Second, three mediation analyses (one per group) assessed the predictor/mediator role of the variables that met significance in the regression analysis.Outcomes & Results: Both cognition and index finger pointing were direct longitudinal predictors of further expressive language skills in the autism group. In TD and HR groups this relation was mediated by age. Conclusions & Implications: Findings highlight the role of age in communicative development, but suggest a key role of cognition and index finger use in the longitudinal relationship between pointing gestures and expressive language development in children with autism. This has important clinical implicationsThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

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.