Sophie Williams – July 19th 2014
A recent study in Atlanta has shown that some babies who display early symptoms of autism spectrum disorder (ASD) seem to be able to self-correct at about 9 months of age.The group of babies studied were all from families where there was already and autistic sibling and therefore a greater chance of ASD.
The study investigator Warren Jones, PhD, director of research at the Marcus Autism Center, Children’s Healthcare of Atlanta, explained, ‘the difference we observed in the developmental profiles of infants who were later diagnosed with autism relative to those infants who show some symptoms of atypical social development but who do not meet full diagnostic criteria for ASD. These infants have vulnerabilities, but the vulnerabilities are not so concerning as to warrant diagnosis, and [it is] these infants who have a more positive prognosis than infants later diagnosed with autism.’
Dr Jones and colleague Ami Klin published an earlier study in 2013 published in Nature and reported in Medscape Medical News, in which they compared eye-tracking in babies from 2 to 24 months. In ten sessions over this period the infants were shown videos of a caregiver. The researchers focused on where the babies looked and how engaged they were with the caregiver. The researchers charted the eye movements of the babies, focusing on how often the baby engaged with the eyes and mouth of the caregiver as well as how much time was spent looking at the non human surrounding areas.
Mr Jones explained that before a baby can walk they are exploring the world by looking at it. The decline in ‘eye-looking’ with infants who go on to be diagnosed with autism begins as early as the second month of life until 24 months.
In this earlier study they were able to correctly predict that the babies with a decline in eye fixation from the second month to six months of life would go on to be diagnosed with ASD by the ages of 24 and 36 months of age. Dr Jones also found that the child’s level of disability at ages 24 and 36 months of age could also be predicted by this decline in eye fixation.
In the latest analysis Dr Jones and his team looked at 18 infants with no signs of ASD at 36 months and 10 infants who had ‘shadow’ ASD, known as broader autism phenotype, or BAP. These babies typically do not go on to meet the full ASD criteria as they develop. What was of most interest were the 9 babies who initially showed eye decline but who then shifted out of this pattern and by 18 months spending an increasing amount of time eye watching.
Dr Jones made the point that, ‘Eye-looking is neither causing nor correcting autism, it’s a marker: a manifestation of the derailment of typical social development.’ However an area of real interest is this shift from non engagement back to more typical eye tracking.
Dr Jones explained in Medscape Medical News, ‘some infants change their behavior and ultimately end up with more social skills than their affected siblings. We need to understand the underlying neurobiology that accompanies these changes in early development, and being able to observe and quantify these differences is the first step.’
Laura Klinger, PhD, University of North Carolina TEACCH Autism Program, Chapel Hill was asked by Medscape Medical News, to comment of the findings, ‘This is truly one of the first datasets we’ve had where we see differences at 2 months, where one group ends up correcting and not having atypical behaviors later on in life, whereas the other group does not.’
Dr Klinger said that the main focus on this years IMFAR meeting would be to promote the earlier intervention of Autism, ‘Researchers around the globe have been looking at whether we can identify early signs of autism in the first year of life to promote earlier and earlier intervention.’