Dr. Greene, my 13-month-old daughter has been developing a habit of banging her head. She seems to do this only when frustrated, upset or excited -- and will then bang her head on furniture, the floor or even on me!! I am concerned that there could be a medical reason for this. Can you please advise on how to treat this habit; she is otherwise behaving quite normally.
Thank you.

There are moments in a child's development that engender fear in her parents: those weeks before she was born when we wonder if she will really be okay, those moments after you have handed her car keys and she drives off with her boyfriend. For parents whose children develop head banging, this is one of those moments.

Every week someone mentions this concern to me (usually in an off-hand way) and then watches to see if I am alarmed. The unspoken fear: autism.

Up to 20 percent of healthy children are head-bangers for a time (Journal of the American Academy of Child Psychiatry, Jul 1983). Head-banging appears in the latter half of the first year of life and generally ends spontaneously by four years of age. Boys are three or four times more likely to be head-bangers than girls.

The child seems compelled to rhythmically move his head against a solid object such as a wall or the side of a crib. Often he rocks his entire body. For most children it occurs at sleepy times or when upset (often as part of tantrums). This behavior can last for minutes at a time -- or sometimes for hours. It can even continue once the child has fallen asleep.

Parents' fear of autism makes sense. Head-banging, head-rolling, and body rocking are each far more common in autistic children. But these rhythmic motor activities are also normal behaviors in healthy infants and young children (and young monkeys for that matter!). This behavior is abnormal, though, if it persists beyond the early years. Any child who is still head-banging beyond three years of age deserves further evaluation.

How can one tell if the head-banging is a part of normal development or an early sign of autism?

Researchers at Cambridge University have found an easy and early way to detect autism. Three hallmark behaviors are the key signs:

1. Lack of pointing -- by fourteen months of age most children will point at objects in order to get another person to look.
2. Lack of gaze-following -- by fourteen months, infants will often turn to look in the same direction an adult is looking.
3. Lack of pretend play -- by fourteen months children will begin to play using object substitution, e.g. pretending to comb the hair with a block.

All three behaviors are typically absent in children with autism.

If a child begins even one of these three behaviors by 18 months, the chances of ever developing true autism are vanishingly small. (British Journal of Psychiatry, Feb 1996)

Why do kids without autism bang their heads?

Many theories have been put forward to explain this common behavior. Perhaps the rocking and even the head-banging provide a form of pleasure related to the movement. This joy in movement is called our kinesthetic drive. All infants are rocked by their mothers when they are carried about in utero. Later on, they enjoy being held and rocked in parents' arms. Movement activities continue as kids grow: the pleasure of jump rope, swings, slides, amusement park rides (bumper cars!) and dancing. These activities all engage the vestibular system of the brain.