THURSDAY, Jan. 26 (HealthDay News) -- Infants younger than a year old who are at risk of developing autism may already have telltale brain responses when another person looks at or away from them, the results of a new study indicate.
The researchers say that the findings suggest that assessing brain responses in infants as young as 6 months may one day help predict whether they'll develop autism at a later age. Currently, firm diagnoses of autism are made only after a child is 2 years old, according to the study in the Jan. 26 online edition of Current Biology.
"Our findings demonstrate for the first time that direct measures of brain functioning during the first year of life associate with a later diagnosis of autism -- well before the emergence of behavioral symptoms," study author Mark Johnson of Birkbeck College, University of London, said in a journal news release.
The study included infants aged 6 to 10 months who had an increased risk of developing autism because they had an older brother or sister with the disorder. The researchers monitored the infants' brain activity while they viewed faces that switched between looking at them and looking away from them.
Previous research has shown that characteristic patterns of brain activity occur in a normal response to eye contact with other people, a response that's crucial for face-to-face social interaction. Older children with autism have unusual patterns of eye contact and of brain responses to social interactions that involve eye contact.
This study found that the brains of the infants at risk of developing autism already process social information in a different way than typically developing children.
"At this age, no behavioral markers of autism are yet evident, and so measurements of brain function may be a more sensitive indicator of risk," Johnson said.
However, the researchers noted that not all the babies who showed these differences in brain function were later diagnosed with autism, and vice versa. Brain-function measuring would need to be further adjusted and used alongside other methods to serve as an accurate predictor of autism in a clinical setting, the researchers said.
The U.S. National Institute of Neurological Disorders and Stroke has more about autism.
-- Robert Preidt
SOURCE: Current Biology, news release, Jan. 26, 2012
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