Well this has been quite the week for anyone interested in ADHD. As the New York Times reported on Sunday, the number of children diagnosed with ADHD has risen by 41% in the last decade. Clearly there is something going on here. While this statistic has gotten a great deal of publicity, it seems to me people aren’t quite sure what to do with it. If other illnesses, say, cancer or cholera increased by 41% in 10 years there would be a massive mobilization on all fronts. We wouldn’t just treat symptoms. We would take a hard look at environmental factors. We wouldn’t assume that better screening was catching cases that have always been present. We would know that something radical had changed in the world of children that was causing them harm.
There is no definitive test for ADHD. There is no way to know, for sure, if we are catching cases that have always been present. One hint may lie in the DSM-IV criteria for diagnosing ADHD which requires impairment caused by ADHD symptoms. In other words, if ADHD-type behavior and thinking causes no impairment for the individual, then there is no diagnosis.
Have we changed the environment and our expectations of children, especially boys under 10, significantly in the last 10 years? Is their world different enough that their normal, natural behavior is now an impediment to their success in school and life? Or, are they actually behaving differently and there is something vital to ideal development that has disappeared from the typical life of children, especially young children.
I would love to hear Dr. Rostain’s take on all the above questions. If this were a regular university class with live lectures, I am fairly certain that some of this week’s lecture would have been devoted to the recent CDC report. One of the major drawbacks of this type of Massive Open Online Course (MOOC) is that everything is prerecorded, and pre-formulated. While students have been discussing the latest statistics in the online forums, the instructor hasn’t officially given us his analysis of the data. Although it would increase the instructors’ workloads, I think MOOCs would benefit from weekly written or video blog posts by their instructors — tying the prerecorded course materials to recent headlines and perhaps to student concerns from the forums.
This week’s lecture and readings are about the neuroanatomy of ADHD. Although issues with the orbital prefrontal cortex and its control of working memory and executive functions get all the publicity, there are two other regions involved with ADHD. The basal ganglia, which is responsible for motor coordination and procedural knowledge, and the cerebellum, which controls movement and cognitive processes that require precise timing, are also affected. The three different types of ADHD, inattentive, hyperactive-impulsive, and combined, correspond with different levels of impairment in these three different brain regions. The lecture was dense with medical terms and brain anatomy and I’ll have to watch it a few more times.
There is a 3-10% reduction in the regional volumes of all three of these brain regions in people with ADHD. In people diagnosed with ADHD these regions work less effectively and efficiently. Now, here is the kicker, drugs increase the neurotransmitters norepinephrine and dopamine in these areas to help them work better but they do not change the biology of the areas. They do not make these brain areas larger and only make them more effective on a temporary basis when the drugs are present. I suspect that although they can cause immediate relief from some ADHD symptoms, drugs are not the best way of treating ADHD, especially in young children with rapidly growing and changing brains.
We know from the London cab drivers study that our brains can physically grow to keep up with the demand to learn new and specialized information. Thomas Elbert’s study of the brains of violin players shows that our brains change to conform to the current needs and experiences of the individual. Changing our children’s environments and what they do with their time may help their brains, at least in some cases, literally grow out of ADHD. Personally I think that the decrease in recess and child-directed play, especially outside play, needs to be taken more seriously. The lowering of the age for teaching formal academics combined with the child abduction and molestation fears that keep kids supervised and inside have changed the childhood experience. Add in the rampant lack of sleep that can create ADHD-like symptoms and it is no wonder diagnoses of ADHD are increasing. Perhaps instead of increasingly medicating childhood we should bring back PLAY, and regular bedtimes.