Joint Attention Revisited: Examining heterogeneity among children with autism

Background: The joint attention (JA) deficit in autism has been well established. JA is predictive of language abilities and may be a pivotal skill necessary for language development. Yet some children with autism display JA abilities. Objectives: This study examines the heterogeneity among children with autism in order to determine how language abilities of children who exhibit JA skills compare to children with similar chronological and mental ages but no JA skills. Methods: Thirty-four children with autism (confirmed by the ADOS and ADI-R) were grouped according to their ability to respond to JA. They were administered the ADOS—Module 1, the ADI-R, the Preschool Language Scale (PLS-4) and the Mullen Scales of Early Development. Module 1 of the ADOS has a JA probe used to place children in the Yes-JA group or the No-JA group. The two groups of children were then compared. Chronological age (CA), nonverbal mental age (MA), and total language age equivalent score were examined. Results: There were 17 children in the Yes-JA group and 17 in the No-JA group. Findings showed that the groups were not significantly different with regard to CA (mean= 42.88 and 42.71 months) or MA (17.06 and 14.06 months respectively) but had significantly different language scores (mean= 16.65 and 9.88 months). Conclusions: This study demonstrates that there is more to JA acquisition in autism than CA or MA. Even from a sample of children with autism who had low mental ages (mean 15.56, range 4-30 months), half of the group demonstrated an ability to respond to JA. This group had considerably superior language than the group without JA. This supports the theory that JA is a pivotal skill for learning language. Children with autism who have JA skills may take a different developmental path then those without, resulting in enhanced language development.