The "ADHD Gene" and What it Means for Your Child

by Wendy Burt-Thomas

Scientists have discovered that a dopamine receptor gene may help cause Attention Deficit Hyperactivity Disorder (ADHD). According to Dr Philip Shaw of the U.S. National Institute of Mental Health's Child Psychiatry branch, those with a variant of the gene have a greatly increased risk of having ADHD. On the other hand, not all children with ADHD have the gene.

“This gene can be found in about 1 out of 4 people today,” explains Nick Tasler, author of “The Impulse Factor: Why Some of Us Play it Safe and others Risk it All.” “It's disproportionately common in kids with ADHD and those that suffer from addictive disorders.”

How does the gene work?

Contrary to what many believe, production of dopamine, which regulates things like movement and balance, is actually decreased in children with ADHD. This is explains why stimulants (like Ritalin and caffeine) work well for many children with the disorder, as it stimulates production of dopamine. It may also explain why adults with ADHD have a much greater risk of abusing stimulant substances like cocaine, nicotine and methamphetamine, all of which improve dopamine function, making the user “feel better.”

Interesting to note: Dr. Shaw's team found two positive correlations in children with the dopamine receptor gene. Firstly, children with the risk gene tended to be a bit more intelligent than those without it. Secondly, as they aged, the children tended to regain thickness in a once-thin tissue in certain areas of the brain that control attention, thereby improving significantly.

Understanding ADHD

“A child's cognitive skill set (underlying tools that enable us to focus, think, plan, prioritize, remember, etc.) is made up of things like auditory processing, visual processing, short and long-term memory, comprehension, logic and reasoning, and attention skills,” explains Dr. Ken Gibson, author of “Unlock the Einstein Inside: Applying New Brain Science to Wake Up the Smart in your Child.” “In children with ADD or ADHD, the weakest cognitive skill is attention, although other areas tend to suffer as well.

There are three types of attention that can be affected: sustained, selective and divided. In general, they are described as:

• Sustained: Allows the child to stay on task for a long period of time

• Selective: Prevents the child from t being easily distracted

• Divided: Allows the child to do more than one thing at a time

In children with ADD, the frontal cortex (surface) of the brain has more difficulty using glucose and less blood flow than in people without ADD. The frontal cortex inhibits impulses, initiates behavior, and controls working memory. When underactive, the ability to screen out irrelevant stimuli is reduced, and the individual pays attention to everything. This results in poor regulation of the motivation system and makes staying on task difficult without immediate rewards.

1   2  Next Page >>