Infant Head Lag May Raise a Red Flag for Autism

November 02, 2012
A simple diagnostic test may help parents and pediatricians identify babies at risk for autism as early as six months of age.

Experts agree that early intervention in children with autism can lead to better outcomes later in life. Typically, autism is not diagnosed until age three or four, when delays in speech and social interaction become evident. New research by Dr. Joanne Flanagan and Dr. Rebecca Landa, director of the Center for Autism and Related Disorders at the Kennedy Krieger Institute, has identified a simple test that can raise a red flag for autism as early as six months.

In the study, a simple “pull-to-sit” test was given to a group of infants with a family history of autism. Researchers looked at head lag in these babies at 6, 14, 24, and 30 months of age. They found that 90 percent of subjects diagnosed with autism had exhibited head lag as infants; 54 percent who met criteria for social and communication delay had exhibited head lag as infants; and 35 percent of children not meeting the criteria for social or communication delay or autism had exhibited head lag at six months.

In a subsequent study, the head-lag test was given only to six-month-olds. The researchers found that the high-risk infants were more than two times as likely to display head lag as the low-risk infants, further suggesting that head lag is more common in infants at risk of developing autism.

“When we see these kinds of indicators that development is disrupted so early in life, we really have a huge advantage,” Dr. Landa says. “We will not have to wait until after the first birthday—after seeing that first words are not emerging—to begin taking action.”

“People think about infancy and ask, ‘What can we do?’” Dr. Landa says. “Actually, there is a lot you can do with an infant to help him with motor skills development and to begin to understand communication and social interaction, and how to play. We teach parents how to use certain strategies with their babies during everyday activities—feeding, bathing, diapering, and playing—and how to recognize the little steps that signify progress.”

This important finding has led to the recent funding of related research. Two subsequent studies will examine in depth the relationship between motor development and social and communication skills.

Dr. Landa hopes that every parent of a six-month-old who learns about this research will try the head-lag test. “It’s very easy for doctors and parents to do this test in babies six months and older,” Dr. Landa says. “If we know a baby has increased genetic risk factors for autism and we see the head lag, we should refer the baby for further developmental workup, monitor the baby’s development, and make sure parents learn strategies for helping the baby to develop motor control.”

The “pull-to-sit” test for head lag is performed with the baby lying on his back. He should be able to control his neck muscles when gently but firmly pulled up by the arms to a sitting position. His head should follow his torso and not lag backward.

Many babies who show head lag do not go on to develop autism or other social or communication problems. “For some, the motor problem may be very transient, disappearing in the first nine months,” Dr. Landa says. “But don’t ignore it. Talk to your pediatrician. If it is a sign of delay, early intervention can improve the outcome.” She adds, “We want intervention to begin when brains are more malleable and still developing their circuitry.”

To learn more about this research and see how to perform the “pull-to-sit” test, visit

Tips for Parents

The “Pull-to-Sit” Test for Head Lag

This test is recommended for babies over the age of 6 months with a family history of autism.

  1. Place the baby on his back on the floor.
  2. Kneel over the baby and make eye contact.
  3. Gently tug on the baby’s arm to give him a cue.
  4. Firmly but gently pull the baby up by his arms to a sitting position.

If the baby is distracted, be sure to get his full attention before beginning the test. The baby’s head should follow his torso up and not lag backward. If the head does appear to lag, be sure it’s not just that the baby is trying to keep an eye on something behind him.

If the baby continues to exhibit head lag after doing the test a couple of times, have a pediatrician examine the baby for other signs of developmental delay.

To learn more about current research initiatives at the institute, visit

Bradley L. Schlaggar, M.D., Ph.D., Named President and CEO of Kennedy Krieger Institute

We’re thrilled to welcome Bradley L. Schlaggar, M.D., Ph.D., to the Kennedy Krieger family as our next President and CEO.

Learn more.


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