Biology 202
2000 First Web Report
On Serendip

According to the US Surgeon General, the definition of ADD is a person who has a combination of at least six symptoms of inattention. These include forgetfulness, often losing objects, reluctance to do difficult work, making careless errors, difficulty sustaining attention, difficulty organizing, and easily distractible. (1). ADHD is considered to be a similar disorder the symptoms may or may not include those for ADD but they must include symptoms of hyperactive behavior. These descriptions are of course very subjective. They would be abnormal in comparison to a person of a similar age/gender/intelligence. Thus a normal toddler would be expected to be very active and distractible in comparison to a teenager and this natural behavior should not be taken as a symptom of ADD. These problems are not; as was once thought things that children will grow out of. They were once thought to be outgrown due to the difference in the behavior of adults with the problem. Adults tend to be less hyperactive and often develop some coping mechanisms. People with this disorder struggle for their entire life to behave normally.

Most people with ADD are born with it. The evidence that it usually runs in families indicates it is a genetic disease. Research into the brain chemistry has found a gene that is involved in a lack of dopamine. "ADHD children differed from controls in that the 7-fold repeat form of DRD4 occurred significantly more frequently than in the control sample. This form of the receptor has previously been shown to mediate a blunted intracellular response to dopamine." (2). The people who are not born with ADD usually develop it due to frontal lobe damage or certain toxins, such as lead, that cause brain damage.

The portions of the brain that are used for executive functions are the same portions of the brain that show abnormalities in people born with this ADD. Magnetic resonance images were used to study brain shape. "Two anterior regions, the rostrum and the rostral body, were found to have significantly smaller areas in the ADHD group." (4). "Total brain volume was 5% smaller in the ADHD boys, and this was not accounted for by age, height, weight, or IQ." (5). In studies of executive function, it was found that during use of the executive function various portions of the cinglet were active. The testing was done using PET tests of the Stroop method.(7). People that develop this disorder due to brain damage are found to have lesions in the frontal lobe in the same region that the executive function and ADD brain abnormalities are found.

There is no cure for ADD or any executive dysfunction; treatment must be continued for life. In people with ADD, the most common treatment is stimulants such as Ritalin. The theory is that it enhances the delivery of dopamine, which ADD sufferers produce in too small amounts. There are numerous problems with using only this treatment. One of them is the lack of a study into the effects of long term stimulant use. There are side effects from stimulants as well. Another problem is a tendency to develop a dependence on the drugs. Often, as adults, they are taken off this medicine and encouraged to live without it. The change from having this aid to figuring out how to deal with the problem on your own is difficult. Other disorders caused by problems with executive functions including injuries are treated in a more systematic way. Rather than treating the symptoms, the person is encouraged to develop other parts of the brain. They are trained to think in ways that gets around the damaged areas. If the damage is severe, there are computer systems similar to palm pilots that can help. These computers are easily carried; they have the ability to store complex schedules, the placement of items, and remind the user when it is time to do something. These machine even have a limited ability to make decisions for the user. (6).

Treatment of ADD as an executive function disorder would mean teaching the person how to take advantage of their brain. This would include special classes, controlled schedules and routines. This would be more work for parents and schools with ADD children but it would enable the children to function well as adults. The evidence for the drugs helping among especially among children is high. So this does not mean the end of treatment with the use of drugs it means additional treatment, which will decrease the need for help as adults.

WWW Sources

2)Attention-Deficit Hyperactivity Disorder-Most Cited Research

3)The Syndrome of Nonverbal Learning Disabilities

4)Attention-Deficit Hyperactivity Disorder-Most Cited Research, quantitative morphology of the corpus callosum in attention deficit hyperactivity disorder

5)Attention-Deficit Hyperactivity Disorder-Most Cited Research, quantitative morphology of the caudate nucleus in attention deficit hyperactivity disorder

6)The Planning and Execution Assistant and Trainer

7)Conflict, Target Detection and Cognitive Control

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