May 17th, 2012
01:49 PM ET
Early research suggests that if a 6-month old baby has "head lag," or weak head and neck control, it may be an early sign of autism or another language/social developmental delay.
The test is simple – babies who are lying on the floor are pulled up into a sitting position. If the baby's head is not moving forward as you pull the baby up, it's a sign of weak head and neck control.
Researchers already know that head lag could be an early sign that a child's nervous system is not developing correctly. They've seen this in children with cerebral palsy and preterm infants, for example. But so far it had not been documented in children with autism.
A group of 40 babies were tested at 6 months. Ten children were later diagnosed with ASD at the age of 3. Nine of those 10 babies had head lag when they were 6 months old.
More than half of the children (54%) who were later diagnosed with language or social developmental delays but not autism also had head lag at 6 months, says Rebecca Landa, one of the study authors and the director of the Center for Autism and Related Disorders at Kennedy Krieger.
In a second study that compared 20 high risk babies to 21 low-risk babies, 75% in the high risk category showed signs of head lag at six months compared to only 33% in the low-risk group.
Landa acknowledges that this research, presented Thursday at a meeting of the International Society for Autism Research in Toronto, is very preliminary and needs to be confirmed in larger studies.
She also cautions that weak head and neck control doesn't automatically mean your baby will develop autism. But, Landa says, if you already have a child with autism and your baby is showing this kind of problem, you should take the child to see a specialist.
"If you don't have a family history of autism, and your child had head lag at 6 months - it might be something else, or might be nothing, but it's important to check it out," she says.
The goal is to identify a child with autism as early as possible so therapy can start early.
"We don't want to wait until children are 1 or 2 when they are more likely to show symptoms of autism."
Alycia Halladay, director of research for environmental sciences at the advocacy group Autism Speaks, says this is a very important study and deserves replication. She says it's too early to consider head lag a diagnostic marker, it's one of many red flags that parents may notice very early in development and something a doctor can easily check out.
Halladay, who was not involved in the research, says "this provides something that parents can bring to their doctors beyond just a concern."
Landa says she doesn't want to scare every parent into thinking their child may have autism because their little one has poor postural control, especially because in some children the problem goes away.
However, this is a simple test that doesn't cost anything, doesn't hurt a child, and - if a child were referred to therapy - doesn't hurt a child but can enrich their development, with or without a subsequent autism diagnosis.
Landa says parents can easily be trained to help their baby improve head and neck control. She suggests Googling "tummy time," which can lead parents to a lot of good information on fun and supportive tummy time exercises to help build their baby's neck muscles.
She also suggests sitting babies up, holding babies at the hips and slowly rocking them from side to side - just enough so that the baby leans to the center, which she says activates the core muscles so the baby stays balanced. Babies love it, especially if you sing a song while doing this.
About this blog
Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.