Causes of Attention-Deficit Hyperactivity Disorder (ADHD)

Attention-Deficit Hyperactivity Disorder (ADHD) has been clinically researched for over thirty-five years. Various labels have been utilized to reflect two basic themes - the predominant symptom of hyperactivity and the clinical assumption that ADHD is related to a neurological dysfunction. Thus, early labels such as "Hyperkinetic Reaction in Childhood", "Minimal Brain Damage", and "Minimal Brain Dysfunction" were used to describe the condition. As research accumulated and better neurological assessment equipment surfaced, professionals began to understand the complex nature of Attention-Deficit Hyperactivity Disorder (ADHD), its' symptoms, and how it can be treated.

Attention-Deficit Hyperactivity Disorder (ADHD) is caused by neurological rather than parental, social, or emotional causes. The cause of Attention-Deficit Hyperactivity Disorder (ADHD) has been linked with the brain's chemical system, not it's structure. Thus, Attention-Deficit Hyperactivity Disorder (ADHD) is a problem with brain chemistry - not brain damage or injury.

The brain uses multiple chemical substances for operation, regulation, and communication. These chemicals, called "neurotransmitters", serve various functions in the brain. Three neurotransmitters have been linked to behavioral and emotional conditions: Dopamine, Serotonin, and Norepinephrine. If we imagine using a "dipstick", like the dipstick used to check oil/transmission fluid levels in our automobile, we might be able to check the neurotransmitter levels in our brain, finding which neurotransmitters are low, within the normal range, or high. Low levels of Serotonin, for example, are linked with clinical depression and for that reason, modern antidepressant medication increases the availability of the Serotonin neurotransmitter in the brain.

Attention-Deficit Hyperactivity Disorder (ADHD) appears related to two neurotransmitters - Dopamine and Norepinephrine. Neurotransmitters are used by the brain to stimulate or repress stimulation in brain cells. To pay proper attention, the brain must be adequately stimulated. To have proper control of our impulses, areas of the brain must be adequately controlled, repressed, or slowed down. In ADHD children, both systems of stimulation and repression are not working correctly. Some studies suggest that ADHD Children/Adults may have only ten to twenty-five percent of these two neurotransmitters found in the normal brain.

Inattention and distractibility appear to be related to low levels of Norepinephrine. ADHD Children/Adults can't judge which things in their environment are important and which should be ignored. ADHD Children/Adults often feel the flight path of a fly in the room is as important as the teacher's algebra lesson. To the ADHD Child/Adult, everything on the desk is equally interesting and worthy of attention. Low levels of Norepinephrine also make it very difficult for ADHD Children/Adults to sustain their focus on a task, plan ahead, and understand such concepts as sequence and time.

The impulse and behavior problems found in Attention-Deficit Hyperactivity Disorder (ADHD) appear related to low levels of Dopamine in the brain. When dopamine levels are normal, we can repress the urge to do or say something in public, grab something interesting on a desk, blurt out our opinion, or touch/poke someone who has just walked within our physical range. Low levels of dopamine in the brain makes control of impulsive behavior almost impossible in the ADHD Child/Adult.

In treatment, medications effective with ADHD Children/Adults are those which alter levels of Dopamine and Norepinephrine. Stimulate medications (Ritalin) are known to increase the production of these two neurotransmitters - boosting their levels into the normal range and producing increased attention and decreased impulsivity. Other medications with similar actions, such as antidepressant medications, can also be of use in the treatment of ADHD Children/Adults.

The many symptoms and behaviors found in ADHD Children/Adults are linked to the various levels of these two neurotransmitters. ADHD is diagnosed in children and adults by recognizing the patterns and symptoms found in the condition. This paper will explore the symptoms associated with Attention-Deficit Hyperactivity Disorder (ADHD).

[ Causes ] [ Diagnosis ] [ Behavioural Patterns ] [ Discipline & Management ]

Written by Joseph M. Carver, Ph.D.,Clinical Psychologist Please visit Dr. Carver's website for more articles.