Exploring Patterns of Change In Social Attention In Young Children with Autism Spectrum Disorder

Background:  Research on early social communication development in young children is needed to assist in more accurate and earlier identification of autism spectrum disorder (ASD), which will allow for earlier intervention and improved outcomes. Research has shown that social attention deficits such as difficulties orienting to social stimuli and developing dyadic and triadic gaze patterns are among the earliest symptoms of ASD and are present across the 2^nd year of life (Dawson et al., 1998), but the deficits may become easier to detect late in the 2^nd year of life (Chawarska et al., 2007; Landa et al., 2007; Gamliel et al., 2009; Paul et al., 2008).  Many of the studies examining social attention in young children have included high-risk samples and further research is needed to examine social attention in children under 18 months of age using a prospective design with a general population sample.  

Objectives:  The purpose of this study was to determine if children with ASD show distinct profiles early (between 12-17 months of age) and late (between 18-24 months of age) in the 2^nd year, compared to children with developmental delay (DD) and typical development (TD). Changes in social attention in all three groups across the 2^nd year of life were also examined to better understand developmental patterns of social attention in children with ASD as compared to children with DD and TD. 

Methods:  Participants were from the longitudinal prospective study of the FIRST WORDS^® Project and included 89 children categorized into one of three diagnostic groups; 32 diagnosed with ASD, 25 with DD in which ASD was ruled out, and 32 with TD. Each of the participants received at least two Behavior Samples; one between the ages of 12-17 months and one between 18-24 months.  Archived videotaped behavior samples of the Communication and Symbolic Behavior Scales (CSBS; Wetherby & Prizant, 2002) were coded using the Observer^® Video-Pro software by Noldus Information Technology, allowing for precise measurement of social attention behaviors. 

Results:  Results indicated that social attention skills differentiated children with ASD from children with TD early and late in the 2^nd year. Furthermore, the pattern of social attention seen across the two time points indicated that diagnostic features of social attention were seen early in the 2^nd year of life in children with ASD and these deficits increased over the 2^nd year of life. 

Conclusions:  The findings of this study suggest that a deficit in social attention is an early symptom of ASD that may be present but more subtle early in the 2^nd year of life and become more apparent late in the 2^nd year of life. Therefore, it is important that ASD not be ruled out under 18 months of age and children be screened between 18 and 24 months of age as recommended by the AAP (2007).