The Influence of Social Communicative Abilities on Language Development in Children At Risk for Autism Spectrum Disorder: A Prospective Longitudinal Study

Background:  Delayed language development is commonly found in young children with autism spectrum disorders (ASDs). The slower acquisition of spoken words is often what first prompts parents to consult a primary health care professional. Concerns about the language development of their child are amongst the most frequently reported parental concerns during the first years of life. Next to its role in the recognition of ASD, early language ability is also related to long-term outcomes for children with ASD. With the recent emphasis on early intervention for young children with ASD to optimize their outcome, language development can be the subject of these intervention programs. In addition, a better understanding of factors that underlie, facilitate, and predict language acquisition in ASD would allow for the refinement of targeted early interventions. Preverbal social communicative skills that have been associated with language development in both typically developing children and in children with ASD are: imitation, joint attention, and pretend play.

Objectives:  The current study investigated the influence of preverbal social communicative abilities on language development between 2 and 4 years in 39 children at risk for ASD, recruited from a screening study in day-care centres.

Methods:  Of the 39 children in this study, 13 children were diagnosed with ASD. The remaining 26 children screened false positive for ASD. Data were collected at three time points, when children were on average 27, 37, and 49 months old. Language development was assessed at each time point with the Receptive Language and Expressive Language subscales of the Mullen Scales of Early Learning (Mullen, 1995). Social communicative abilities were once assessed, at the intermediate time point. Imitation was examined using the Preschool Imitation Praxis Scale (PIPS; Vanvuchelen, 2009), joint attention skills were measured with the Early Social Communication Scales (ESCS; Mundy et al., 2003), and pretend play was assessed using the Test of Pretend Play (ToPP; Lewis & Boucher, 1997).

Results:  Conditional latent growth curve modeling showed that children with ASD had a smaller growth rate for their receptive language development between the ages of 2 and 4 compared to non-ASD cases. Children with ASD also had a marginally significantly lower age equivalent for expressive language at age 2. Whereas pretend play was most closely related to concurrent measures of receptive language ability, the individual differences in growth rates for both receptive and expressive language were most strongly associated with procedural imitation and the ratio score of higher level behaviours to total amount of initiations of joint attention.

Conclusions:  Within an at-risk group, children with ASD were significantly different from non-ASD children in their growth rate for receptive language between the ages of 2 and 4. Since especially imitation and joint attention skills were related to growth rates of language development, enhancing these skills might be an important element of early intervention programs to promote communicative competence in young children at risk for ASD, whether or not they receive a diagnosis of ASD later on.