Educators educating Educators

Jan 19

ADHD Brain Differences

“Boy, what ever you is and where ever you is, don’t be what you ain’t, because when you is what you ain’t, you isn’t.” ~ Uncle Remus




AD/HD Structural Differences using MRI - 
Magnetic Resonance Imaging

AD/HD vs Normal Growth

AD/HD vs Normal Development 2

AD/HD Graph AD/HD vs. Normal Development

Neurology Today, 7:24, December 18, 2007


Slight reduction in size in 4 regions of the brain: See below to view some brain scans showing brain areas affected by AD/HD


1. Corpus callosum-connects the left and right hemispheres of the brain


2. Basal ganglia (AD/HD symptoms of mood regulation and controlling impulsive outburst


3. Frontal lobe (AD/HD symptoms of organization, time management and decision-making)


4. Cerebellar vermis - connects the two hemispheres of the cerebellum


AD/HD Brain Structural Differences ~ A Neurobiological Disorder


Allan Zametkin, National Institute of Mental Health, 1990

Seminal study proving that AD/HD stems from biological irregularities in the brain


Zametkin proved the biological existence of AD/HD


He established that the brain of a person with AD/HD works differently


Used PET scans to measure brain activity


During activities involving attention tasks, the brains of people with AD/HD ad 10% less activity than the control group


The largest area of inactivity was in the prefrontal cortex, the executive function area

Alan Zametklin

Alan Zametklin

Slide from Alan Zametkin's 1990 study: AD/HD PET Scan

Zametkin's studies are enlightening in the structural differences in the ADHD brain. Brain scan images produced by positron emision tomography (PET) show differences between an adult with Attention deficit Hyperactivity Disorder (ADHD) (right) and an adult free of ADHD (left).

Ad/HD Reduction 2


Brain scans showing brain areas affected by AD/HD

Zametkin 1990


AD/HD Brain Structural Differences

Castellanos & Rappoport


A 10-year study by National Institute of Mental Health


Brains of children & adolescents with AD/HD are 3-4 % smaller “in all regions” than those of children who do not have the disorder


“strikingly smaller” white matter volumes


Smaller frontal lobes, temporal gray matter, caudate nucleus, and cerebellum


“found that the whole brain is affected”

“white matter volume was abnormally small”

“delays in white matter maturation”


Fibers that establish neurons’ long-distant connections between brain regions


Xavier Castellanos & Judith L. Rappoport, Journal of the American Medical Association, October 9, 2002, National Institute of Mental Health



Another study by Alan Zametkin using PET scans on adults with AD/HD discovered that when the subjects concentrated, the level of activity in the front part of the brain (the frontal lobes) decreased from its level at rest


People without AD/HD have an opposite response – an increase in activity in the frontal lobe when they concentrate


This study is generally credited with showing that AD/HD s a biologically based condition



Joel Lubar, University of Tennessee, conducted studies showing that when people with AD/HD concentrate, there is an increase in theta activity (slow brainwaves) in the frontal lobe of the brain this finding corresponds to a lower level of activity in this region



Robert Chabot and his colleagues at New York University found 11 different patterns of QEEG (quantitative electroencephalogram) - a device that measures surface brain wave activity


Chabot also found that some people could be predicted to respond well to certain medications and poorly to others



Daniel Amen conducted testing showing several variations in brain activity in people with AD/HD and has suggested that AD/HD is actually several different conditions, each with a different brain activity signature


“If we can control the attention of the child, we solve the problems of education.” Maria Montessori

This month Ed Tip will examine how to improve students' learning by activating their attention.