ADHD brains may have 'faulty brakes'
February 14th, 2011
05:37 PM ET

ADHD brains may have 'faulty brakes'

Much news about attention-deficit hyperactivity disorder has focused on learning and attention, but here's another important part of this condition: Impairment in motor function.

Two new studies in the journal Neurology explore how brain functions relating to motor control may explain certain ADHD symptoms. They support previous research showing that kids with ADHD have motor control problems and offer new potential targets for treatment in the brain's inhibitory systems.

“If we can understand the systems that are involved, because there’s probably not just one, then we can identify groups of kids that have these symptoms, quantitatively and reliably, and use that information to understand who’s at the highest risk of a bad adult outcome,” said Dr. Donald Gilbert, study co-author and director of the Movement Disorder Clinic and Tourette's Syndrome Clinic at Cincinnati Children's Hospital Medical Center.

The first study showed that kids with ADHD - mainly boys, however - tend to have mirror movements, meaning that when one side of the body moves, the other does too, such that if a finger from one hand is tapping, a finger on the other hand might also move to some extent. The kids with ADHD tended to have more clumsy finger movements of this nature in the study. Such mirror movements are common in very young children, but typically disappear when the child reaches school age; participants in this study were between ages 8 and 13.

And a second study found that children with ADHD have a less efficient "braking system," or the brain circuitry involved in stopping oneself from acting impulsively (the editorial accompanying the studies is called "Faulty Brakes?"). This one used transcranial magnetic stimulation, a technique that applies a magnetic field to cause changes in electrical activity in the brain. This allowed the researchers to measure inhibition in the brain. They found that kids with ADHD were more likely to have inhibitory problems, explaining neurologically what these children tend to experience in school.

"Something catches their attention and they get distracted because they can’t inhibit that stimulus and ignore it," said Dr. Max Wiznitzer, pediatric neurologist at Rainbow Babies & Children's Hospital in Cleveland, Ohio, who was not involved in the study.

Both of these studies are relatively small - the first involved a total of 50 right-handed participants and the second had 98. But the findings are interesting, especially with regard to the transcranial magnetic stimulation experiment, and could be useful for developing new treatments, Wiznitzer said. This kind of research may also lead to subtyping of ADHD based on different underlying brain function in different groups.

But he cautioned that coordination issues aren't necessarily indicative of ADHD, but may also be indicative of other kinds of learning disabilities, Wiznitzer said.

"If you notice that your young child has clumsy motor movements or shaky hands, you should be aware that there may be some problems with learning, attention or impulse control later, and be more vigilant for those problems," Gilbert said.

soundoff (155 Responses)
  1. funcrew

    I've noticed that ADHD boys excel at sports, and the more intense the sport, the better, for example folkstyle, freestyle, and greco wrestling. The ADHD kids dominate the calm, compliant so-called "normal" boys that public educators are so enamoured with. The same trend continues into adult life where the ADHD kids grow up to be trial lawyers, race car drivers, military generals etc. ADHD is only a problem for public school instructors who expect young boys to sit still and listen to their boring BS for 6 hours straight.

    February 15, 2011 at 18:43 | Report abuse | Reply
    • notation

      Then why aren't ALL kids on meds, you moron?

      February 15, 2011 at 19:42 | Report abuse |
    • Kati

      And what about the girls with ADHD?

      June 5, 2011 at 17:07 | Report abuse |
  2. LiberateUs

    ADHD is the next step to human evolution. I have ADHD, and doctors can KMA!

    February 15, 2011 at 19:20 | Report abuse | Reply
    • Jabberwocky

      You don't have ADHD. You have cranial-rectal inversion disorder.

      February 15, 2011 at 19:41 | Report abuse |
  3. adhhdd

    I have add. as a kid i would always mix my words together as i was always trying to talk too fast. i would say that i think in 3D (i was under 10). I also have barely legible handwriting and adderall has done wonders. doubters are idiots. many times i feel like i have multiple streams of consciousness going at the same time.

    February 15, 2011 at 20:54 | Report abuse | Reply
    • stephgob

      I use the "think in 3D" analogy all the time... like a zillion lines of code swirling across a computer screen, then turned into a 3D mess, out of which I try to isolate and focus on on simple thing... that is the ADHD brain for ya

      February 16, 2011 at 17:12 | Report abuse |
  4. sadmom

    My son was diagnosed with ADHD far too late to help him (in high school). Even though he displayed problems all through elementary and jr. high, the school chose to categorize him as an "overly social" child and not in need of academic help, although he never learned to read very well and got average or below average in all academic classes, but excelling in anything physical! By high school, when one doctor finally agreed that he had a problem and prescribed Adderol, he took it for a couple of months, but didn't like being "calm." , – by then he enjoyed being "wired" all the time, and refused to take Adderol after a couple of months. He barely made it through high school, was kicked out of the military for alcohol/drug abuse and mouthing off to his superiors, he has no self-control whatsoever, no filter, and no common sense. He has had many, many relationships with women that last long enough for them to figure out what he is, or for him to tire of them! He has had a very difficult time holding down a job for very long, but a year ago fell into a sales job and has found his niche, finally. [As they say, he could sell ice to eskimos!] My main concern now is his continuing alcohol/drug abuse because it takes all his money, he has no budgeting sense at all, and expects his dad and I to bail him out of every mess he gets himself into. I know eventually it will lead to his downfall in this job as well. Although his dad and I have offered to pay for his counseling, he refuses to go. I can't stand to be around him because he's always so hyper and if things don't go his way, vocally abusive. He's an adult now. I can just walk away and pretend he was never born, or .......what? If someone out there has an answer, please comment. And BTW, the other children are all fine, successful, and happy. He was raised in a very loving home where every opportunity possible was given to him, as was the other children. His problem is clearly chemical.

    February 16, 2011 at 13:14 | Report abuse | Reply
    • dg

      Dear SadMom. I understand. We have almost the exact same situation with our 39 year old. When he was diagoned at 17 with servere ADHD, the doctor gave me a book to read and said "you'll think they wrote this about your son". I decided to read it while my husband was working in the yard and when things pertained to my son, I read them out load. Soon I was reading the entire book out load and my husband grabbed the book and said "When was this written". My son fit every example and had every sympton. He hasn't been able to live a normal life. He has a criminal record and is addited to drugs. Can't hold a job or stay in a relationship. Doctor said back then the pot was his self medication. Now he uses more serious drugs.
      To Others: Weren't there children born prior to the known risk of smoking?
      To Others: Calling people morons and etc. does not help this problem. We don't have to agree with everyone but we should be willing to listen, make our own decisions, and let others make theirs.

      February 22, 2011 at 14:45 | Report abuse |
  5. MR

    Where is the research behind this article? I'd love to read the ACTUAL research report, not the opinion of the news writer.

    February 18, 2011 at 10:44 | Report abuse | Reply
  6. dg

    To all: I apologize for my spelling in my earlier comment. IMy own ADD is showing and 'm too used to Spell Check.

    February 22, 2011 at 14:55 | Report abuse | Reply
  7. シャネル時計偽物


    October 12, 2017 at 20:24 | Report abuse | Reply
  8. Alice Hunter

    I'm an ADD college student. I've been told by my doctors that I have 'Familial Tremors' my hands shake (they worsen with strong emotions such as anger or anxiety), sometimes my arms shake, and on rare occasions even my leg(s) shake without my control. I've been doing a lot of reading and it appears that many other ADD/ADHD people have similar issues. I wonder if they're just extremely common co-occuring issues or if the ADD/ADHD is causing the issue?

    March 6, 2019 at 19:24 | Report abuse | Reply
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