ADHD Research in Children and Adults
ADHD has been receiving considerable attention over the last twenty years in regards to "What is it? Does it really exist? How do you treat it?" Within the last ten years a focus has grown over whether or not an individual will ever outgrow ADHD if they had been diagnosed with the condition as a child.
The latest research has focused on "What does the brain of a research participant with a previous diagnosis look like and how is it different from those with no symptoms of the condition when using brain scanning technology (functional Magnetic Resonance Imaging- fMRI and Computerized Tomography- CT)?"
There is a difference between those with no symptoms and those with a previous diagnosis and symptoms such as restlessness, impulsivity, and difficulty concentrating on tasks, and forgetfulness.
Brain scans suggest a person with ADHD has a smaller prefrontal lobe which is the part responsible for what is called executive functioning. This would be planning, reasoning, and problem solving. Research suggests typically a 10% difference in size. Other parts of the brain involved with learning and reasoning also appear more diminished in size. The smaller right frontal lobe may be the cause of the inattentive behaviors.
There are several chemicals called neurotransmitters that are being researched as to the roles they play in ADHD. One study of just children found excessive amounts of the chemical glutamate in those with a diagnosis of ADHD and less amounts of the neurotransmitters dopamine and norepinephrine. The last two chemicals are mimicked by the stimulants typically prescribed to those with ADHD.
Now here is the question, "Do you ever outgrow ADHD?" The answer is probably not. At least 50% of those with previous diagnosis continue to demonstrate symptoms into adulthood. Also, the frontal lobes do mature as a person ages, but seldom reach the development of those with no previous diagnosis. Finally, it appears that we outgrow the typical childhood symptoms, but symptoms remain and present a somewhat different clinical picture.
The next blog will cover current research on medical and non-medical treatments of ADHD.
Richard Boyd, M.A.
Ash Grove Family Medical Center - 417-751-2100
Dade County Family Medical Center - 417-637-5133