Ambidextrous kids at higher risk for learning problems, ADHD

From NPR's Health blog:

Ambidextrous kids are more likely to suffer from language and learning problems, such as attention deficit/hyperactivity disorder (ADHD), than their right- or left- handed peers.

A new study, out Jan. 25 in the journal Pediatrics, looked at nearly 8,000 children, 87 of whom were mixed-handed. Researchers found that ambidextrous children were twice as likely to have difficulties with language, and by ages 15 to 16, they were twice as likely to exhibit symptoms of ADHD.

While the study doesn't suggest that all mixed-handed kids will develop learning difficulties, researchers concluded that, when combined with learning difficulties, ambidexterity could help identify children at risk for developing more significant problems as they mature.

Shots caught up with the study's lead researcher, Dr. Alina Rodriguez, currently of Imperial College London, to find out more. Here are edited highlights from the interview.


What makes someone ambidextrous? Is it genetic?
We really don't know. Most people are right-handed. [Mixed-handedness] is a rare occurrence. It could be prenatal factors in the womb that affect how the brain develops before birth. But there are others factors, including genetic ones, and we aren't clear on which one it is specifically.

What are the broader implications of this study?
[Someone's] mixed-handedness is a marker of brain circuitry that shows a different pattern than the norm -- what you see in most people. It was the mixed-handed children who had the greatest probability of having stable or more severe ADHD. And ADHD is a complex disorder. So [handedness] would be one of the factors that tells us about heightened risk. Mixed-handedness by itself may not pose any problems at all for the child, but in conjunction with other difficulties and risk factors, it's a red flag to evaluate the child. If in fact, the child does reach the criteria for ADHD they can then get the help they need.

How can children be treated? Can any sort of preemptive action be taken to keep kids from developing more severe learning disabilities and ADHD?
There's a lot you can do, especially if you discover the problem early so that children don't get into a negative developmental trajectory. It's a good idea to give children extra help, but you need to see what works for that particular child in their particular difficulties. Speech therapy is one. Or, for ADHD, behavioral strategies would be positive, so that the child develops guidelines for their behavior. Children with ADHD need structure.

Also, if the child does have a diagnosis of ADHD and the psychologist or pediatrician who is attending finds that that child would benefit from psychopharmacological treatment, then that would then be the best thing for that child.

What does this mean later, in adulthood?
A long time ago, people thought that ADHD was something you just outgrew. But it's now recognized that many people have problems in adulthood of the same type as children and teens. It's important that we recognize this in adults too. It really has an impact on the quality of their daily lives. ADHD is not just a childhood disorder.

Do you have any recommendations for doctors and parents?
I would say that if a child is mixed-handed and shows absolutely no other problems, then don't worry about it at all. Other people in history have been mixed-handed and exceptional -- Leonardo DaVinci, Einstein, and others. It's not something you need to worry about in that sense. But if mixed-handedness is paired with other problems, by all means, seek help