Inflammation may be main driver behind autism, a new study suggests.
Researchers compared the brains of eight children with the developmental disorder and eight children without it.
They found the parts of the autistic children's brains that are crucial to working memory and attention - areas that are impaired in people who have autism - had unusually high levels of a molecule known to trigger inflammation.
The team, led by Tufts University School of Medicine in Boston, Massachusetts, says the findings suggests that drugs that target anti-inflammatory proteins could one day be an effective treatment for autism.
Autism spectrum disorder (ASD) is a developmental disorder in which sufferers have a hard time communicating and with behavior. It encompasses several conditions - including autism, Asperger's syndrome and childhood disintegrative disorder - and symptoms can range from mild to severe.
Children are usually diagnosed by age two after they exhibit signs such as reduced eye contact, not responding to their name and performing repetitive movements.
According to the Centers for Disease Control and Prevention, about one in 59 children has ASD.
Boys are much more likely - up to four times - to have the condition than girls.