Motor Functioning and Language Development in Preschool Children with Autism

Background: Although delays and deficits in language development are diagnostic criteria for Autism Spectrum Disorder (ASD), little is known about the pre-clinical signs related to these deficits. Various researchers have noted delays and deficits in the motor skills of young children with ASD, little attention has been paid however to the role of motor development in the acquisition of language in children with ASD. From an embodied cognition perspective it is proposed that motor functioning and language development are related, and that exploratory behavior and visuospatial cognition are possible mediators of this relationship. This perspective may be fruitful to study the language acquisition in ASD.

Objectives: The objectives of this study were to examine whether (1) early motor functioning can predict later receptive and expressive language development in children with ASD and children at risk for ASD, (2) the relationship between motor functioning and language is mediated by exploration and visuospatial cognition, (3) the relationship between motor functioning and language is moderated by severity of autism.

Methods: Longitudinal relations between early finemotor functioning and language in the fourth year of life were examined in two groups of preschool children: 50 with ASD, confirmed by ADI-R and the ADOS-G, and 120 at high risk for developing ASD. The high risk children failed 3 or more items on the Early Screening of Autistic Traits (ESAT) but had no ASD at the moment of assessment. Motor functioning, visuospatial cognition and language abilities were assessed with the Mullen Scales of Early Learning (MSEL). An observation coding scheme was applied to score several aspects of exploration.

Results: Finemotor functioning predicted language in the ASD and the high risk group. This relationship was mediated by visuospatial cognition in both groups and by exploration in the ASD group. Severity of autism moderated the strength of some of the relations with stronger effects in the ASD group compared to the high risk group.

Conclusions: Early motor functioning, exploration, and visuospatial cognition appear to be predictors of later language development in children with autism. These findings are in support of the embodied cognition theory.  The current study emphasizes the importance of motor assessment for children with ASD and the need for clinicians to consider cognition in general, and language specifically as emergent from multiple interacting systems. Future longitudinal studies are needed to examine the developmental trajectories of ASD and the interrelations between different domains of functioning.