Children with autism have difficulty with social skills and communication. They often behave in restricted and repetitive ways and have what seem like abnormally intense interests.

A widely used medical guide will list autism under a new definition and name, "autism spectrum disorder." The changes will appear in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, to be published in May.

The "spectrum" represents a group of developmental brain disorders, ranging from mild to severely disabling. A milder form commonly called Asperger’s syndrome will no longer be listed as a separate disorder with its own name.

Autism is more common in boys than girls. What causes it is not clear. Scientists are studying genes and possible environmental influences.

Doctors usually cannot confirm a diagnosis of autism until a child is about three years old. Rebecca Landa is a researcher at the Kennedy Krieger Institute and Johns Hopkins University School of Medicine in Maryland. Professor Landa wanted to find out what differences in development might be seen earlier. She led a new study that observed 235 babies between six and 36 months of age.

"At six months of age, the signs of some risk for developing communication and social delays, including autism, include motor delays. Like when you lay your baby on their back and you pull them by the arms gently into a seated position, the baby’s head may nod back behind the shoulders, like poor head control. So that does not mean that the baby is going to have autism, but it does mean the baby needs to have some exercises to strengthen their body. And when they strengthen their body, they are better able to play with toys and engage with people, which then goes on to help them have better outcomes."

By the time a baby is one year old, signs of possible autism include difficulty in using words and not looking eye-to-eye or reaching out to other people. By 14 months, the baby might smile less and use language less. However, Professor Landa says these signs can be so small that they might be missed during a short health exam.

"It’s important for parents to stay tuned in to their children’s development, and if a parent is concerned about a child’s development, for professionals to listen to them."

The earlier parents notice delays, she says, the sooner they can begin doing simple things that may help improve their child’s development. For example: talking to the child about what they are doing, commenting when the child shows them something, and playing simple games that keep the child’s attention.

Children with autism have difficulty with social skills and communication. They often behave in restricted and repetitive ways and have what seem like abnormally intense interests.

A widely used medical guide will list autism under a new definition and name, "autism spectrum disorder." The changes will appear in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, to be published in May.

The "spectrum" represents a group of developmental brain disorders, ranging from mild to severely disabling. A milder form commonly called Asperger’s syndrome will no longer be listed as a separate disorder with its own name.

Autism is more common in boys than girls. What causes it is not clear. Scientists are studying genes and possible environmental influences.

Doctors usually cannot confirm a diagnosis of autism until a child is about three years old. Rebecca Landa is a researcher at the Kennedy Krieger Institute and Johns Hopkins University School of Medicine in Maryland. Professor Landa wanted to find out what differences in development might be seen earlier. She led a new study that observed 235 babies between six and 36 months of age.

"At six months of age, the signs of some risk for developing communication and social delays, including autism, include motor delays. Like when you lay your baby on their back and you pull them by the arms gently into a seated position, the baby’s head may nod back behind the shoulders, like poor head control. So that does not mean that the baby is going to have autism, but it does mean the baby needs to have some exercises to strengthen their body. And when they strengthen their body, they are better able to play with toys and engage with people, which then goes on to help them have better outcomes."

By the time a baby is one year old, signs of possible autism include difficulty in using words and not looking eye-to-eye or reaching out to other people. By 14 months, the baby might smile less and use language less. However, Professor Landa says these signs can be so small that they might be missed during a short health exam.

"It’s important for parents to stay tuned in to their children’s development, and if a parent is concerned about a child’s development, for professionals to listen to them."

The earlier parents notice delays, she says, the sooner they can begin doing simple things that may help improve their child’s development. For example: talking to the child about what they are doing, commenting when the child shows them something, and playing simple games that keep the child’s attention.