Posted on 11/12/2007 2:19:05 PM PST by crazyshrink
In youth with attention deficit hyperactivity disorder (ADHD), the brain matures in a normal pattern but is delayed three years in some regions, on average, compared to youth without the disorder, an imaging study by researchers at the National Institutes of Healths (NIH) National Institute of Mental Health (NIMH) has revealed. The delay in ADHD was most prominent in regions at the front of the brains outer mantle (cortex), important for the ability to control thinking, attention and planning. Otherwise, both groups showed a similar back-to-front wave of brain maturation with different areas peaking in thickness at different times.
Finding a normal pattern of cortex maturation, albeit delayed, in children with ADHD should be reassuring to families and could help to explain why many youth eventually seem to grow out of the disorder, explained Philip Shaw, M.D., NIMH Child Psychiatry Branch, who led research team.
Previous brain imaging studies failed to detect the developmental lag because they focused on the size of the relatively large lobes of the brain. The sharp differences emerged only after a new image analysis technique allowed the researchers to pinpoint the thickening and thinning of thousands of cortex sites in hundreds of children and teens, with and without the disorder.
If youre just looking at the lobes, you have only four measures instead of 40,000, explained Shaw. You dont pick up the focal, regional changes where this delay is most marked.
Among 223 youth with ADHD, half of 40,000 cortex sites attained peak thickness at an average age of 10.5, compared to age 7.5 in a matched group of youth without the disorder.
Shaw, Judith Rapoport, M.D., of the NIMH Child Psychiatry Branch, Alan Evans, M.D., of McGill University, and colleagues report on their magnetic resonance imaging (MRI) study during the week of November 12, 2007, in the online edition of the Proceedings of the National Academy of Sciences.
The researchers scanned most of the 446 participants ranging from preschoolers to young adults at least twice at about three-year intervals. They focused on the age when cortex thickening during childhood gives way to thinning following puberty, as unused neural connections are pruned for optimal efficiency during the teen years.
In both ADHD and control groups, sensory processing and motor control areas at the back and top of the brain peaked in thickness earlier in childhood, while the frontal cortex areas responsible for higher-order executive control functions peaked later, during the teen years. These frontal areas support the ability to suppress inappropriate actions and thoughts, focus attention, remember things from moment to moment, work for reward, and control movement functions often disturbed in people with ADHD.
Circuitry in the frontal and temporal (at the side of the brain) areas that integrate information from the sensory areas with the higher-order functions showed the greatest maturational delay in youth with ADHD. For example, one of the last areas to mature, the middle of the prefrontal cortex, lagged five years in those with the disorder.
The motor cortex emerged as the only area that matured faster than normal in the youth with ADHD, in contrast to the late-maturing frontal cortex areas that direct it. This mismatch might account for the restlessness and fidgety symptoms common among those with the disorder, the researchers suggested.
They also noted that the delayed pattern of maturation observed in ADHD is the opposite of that seen in other developmental brain disorders like autism, in which the volume of brain structures peak at a much earlier-than-normal age.
The findings support the theory that ADHD results from a delay in cortex maturation. In future studies, the researchers hope to find genetic underpinnings of the delay and ways of boosting processes of recovery from the disorder.
Brain imaging is still not ready for use as a diagnostic tool in ADHD, noted Shaw. Although the delay in cortex development was marked, it could only be detected when a very large number of children with the disorder were included. It is not yet possible to detect such delay from the brain scans of just one individual. The diagnosis of ADHD remains clinical, based on taking a history from the child, the family and teachers.
### Also participating in the research were: Kristen Eskstrand, Wendy Sharp, Jonathan Blumenthal, Dede Greenstein, Liv Clasen, and Jay Giedd, M.D., NIMH.
The National Institute of Mental Health (NIMH) mission is to reduce the burden of mental and behavioral disorders through research on mind, brain, and behavior. More information is available at the NIMH website, http://www.nimh.nih.gov.
The National Institutes of Health (NIH) - The Nation's Medical Research Agency - includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.
Of course, what this really proves is that the students with ADHD should be grouped together, and taught with different methods, rather than being “mainstreamed” all together.
Needs a patient teacher too.
Can we still addict them to pharmaceuitical drugs? Will Ritalin sales suffer?
Brain imaging is still not ready for use as a diagnostic tool in ADHD, noted Shaw. Although the delay in cortex development was marked, it could only be detected when a very large number of children with the disorder were included. It is not yet possible to detect such delay from the brain scans of just one individual. The diagnosis of ADHD remains clinical, based on taking a history from the child, the family and teachers.
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That’s a big problem that many people pose. We need an objective diagnosis before giving out medicine to kids
I want to clarify. If the kid is running into walls that’s an extreme clear case and obviously should be treated.
but in today’s society of tv, liberal teachers and parenting methods, we shouldn’t rely on medicine as a quick fix for wholesale behavioral problems.
"Mainstream" is administrator speak for "we're throwing in the towel" or "we need to make room for kids that are relatively more screwed up". At 27, my oldest still has ADHD problems. The San Diego school system did a pretty good job. He has about half his college courses completed toward a degree in geology, but his capacity to handle multiple classes is dragging the process out. My youngest is 20. He has ADHD too, but the Idaho schools failed him in 8th grade (when we moved from San Diego). He seems to be reaching a point where is a ready to launch on academic issues.
we shouldnt rely on medicine as a quick fix for wholesale behavioral problems.
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There you have it in a nutshell. Today’s medical model, as well as parent’s demands, etc., promote treating the symptom, and less the cause. Fix lil Johnny/Susie NOW!
I do not agree however, that the cause here is behavioral. But rather a slight biological anomaly in the brain which reduces the child’s executive functioning. IMO, the behavioral issues are the symptom.
ADHD Bump for later... if I remember...
His attention deficit was so bad that he walked right into a swimming pool at a family Easter gathering. His attention was focused across the yard and not on the ground immediately of ahead. He just passed his written exam for a driver's license last week. I'm still reticent to turn him loose in 2000 lb vehicle on a city street. The license is for supervised driving, not by himself. He needs a "safety" driver to keep him situationally aware at this stage.
IF these patients are already on drugs that may stunt growth, could it be the drugs that are causing the delay? I don’t remember ADD, ADHD, etc. when I was a kid. I can’t believe this is all due to improved methods of diagnosis.
The press release has figures and a link to a Video, MP4 File.
The PNAS article or abstract isn't available yet.
This is terrific! This means that kids with ADHD or ADD have brains that are still soaking up information like sponges and GROWING, while their normal peers are pruning neurons in their brains which have CEASEd growing.
Thank you. The schematics were in the article I posted but didn’t see a link to the video. Thanks again.
so, dammit, it’s not a disease, FGS !!!!! Why do they think it still needs to be “fixed” ?
yes, yes, yes. To me this is just further proof that so-called ADHD is not a “disease”.
Years ago the kids could finish school at 8th grade and go out and get a job that would support them for life - mechanic, tradesman, assembly line work, or whatever - but in today’s world, that’s not possible, unfortunately.
I work in the field of ADD/ADHD and don’t believe it is a disease. ADHD, alcoholism, etc. are trying to be classified as diseases in order to tap into the insurance market...based on the medical model...where the money is.
You are probably one of a few in your profession who’s not a true believer ... I salute you.
There are a few of us. But in a highly liberal profession other voices are often “less heard”. Kinda like the “consensus” in global warming.
I also have disdain for general psych med use believe it or not. Being a psychologist, I cannot prescribe meds, only psychiatrists (MD’s) or med Dr’s can.
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