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.
Researchers at Baltimore's Kennedy Krieger Institute looked at a small sample of babies who were already at high risk for autism because they had a sibling with autism. If a couple already has one child with an autism spectrum disorder there's a nearly 1 in 5 chance that the second child will have autism too. According to the latest CDC estimates, 1 in 88 children in the United States has an autism diagnosis. It's 5 times more common in boys than girls.