Atypical play behaviors in infancy predict autism diagnosis
Posted Oct 27 2008 12:22pm
A review of: S. Ozonoff, S. Macari, G. S. Young, S. Goldring, M. Thompson, S. J. Rogers (2008). Atypical object exploration at 12 months of age is associated with autism in a prospective sample Autism, 12 (5), 457-472 DOI: 10.1177/1362361308096402
A number of research programs are currently examining very early signs of autism. Researchers believe that if they are able to identify behaviors or symptoms that reliably predict the development of autism, these kids could receive early intervention and we may be able to better understand how autism emerges during key developmental periods. I have reviewed some of these studies ( see for example this review of a study of infancy motor asymmetry and autism ). The current study comes to us from the MIND institute at the University of California at Davis. The researchers wanted to examine atypical use of objects during infancy (12 month of age) and explore whether object use during this time predicted the development of autism 1 to 2 years later.
The sample included a high-risk group consisting of 35 non-affected siblings of children with autism and 31 siblings of typically developing kids. 62% of the sample were males. All children were 12 month of age at the time of the first assessment. These children were further evaluated at 24 or 36 month of age via a comprehensive neurodevelopmental battery of tests which included the ADOS.
At 12 months of age, the infants were observed interacting with 4 objects (metal lid, plastic ring, rattle, baby bottle). The interactions lasted 30-seconds each. These interactions were coded for typical and atypical object use. Typical uses at this age would include shaking, banging, mouthing, and throwing. More infrequent, and thus atypical, uses of these toys would include spinning, rolling, rotating, and unusual visual exploration (looking at the toy from odd angles or peripherally).
From the initial pool of 66 infants, 9 eventually met diagnostic criteria for autism (based on ADOS), 10 met criteria for non-asd developmental delay, 47 did not receive any diagnosis (no concern group). There were no differences among these 3 outcome groups in regards to gestational age, ethnicity, or income. However, the percentage of males in the autism group (100%) was significantly higher than in the developmental delay (70% males) and the no concern group (49% males).
In regards to typical object use, the only group difference observed was for “throwing”. Infants who would eventually be classified into the developmental delayed group were significantly more likely to throw the objects than children eventually classified into the autism or no concern groups. However, in regards to atypical object use, the findings were striking. Infants who would eventually developed autism were significantly more likely to engage in all 4 atypical uses (spinning, rolling, rotating, and unusual visual exploration) than kids classified into the no concerns group. In addition, 3 specific atypical object behaviors differentiated kids with autism from those who would develop a non-asd developmental delay. Specifically, kids with autism were more likely to spin, rotate, or engage in atypical visual inspection of the objects, than developmentally delayed kids.
These results indicate that, among children at familial risk for autism, atypical object use during infancy seems to be associated with autism diagnosis during early childhood. Furthermore, this effect appears to be specific to austim --and not to general developmental delays.