Definition of Attention deficit hyperactivity disorder (ADHD):

ADHD is a problem with inattentiveness, over-activity, impulsivity, or a combination. For these problems to be diagnosed as ADHD, they must be out of the normal range for the child's age and development.

Causes, incidence, and risk factors:

ADHD affects school performance and interpersonal relationships. Parents of children with ADHD are often exhausted and frustrated.

Neuroimaging studies suggest that the brains of children with ADHD are different from those of other children. These children handle neurotransmitters (including dopamine, serotonin, and adrenalin) differently from their peers.

ADHD is often genetic. Whatever the specific cause may be, it seems to be set in motion early in life as the brain is developing.

Depression, sleep deprivation, learning disabilities, tic disorders, and behavior problems may be confused with, or appear along with, ADHD. Every child suspected of having ADHD deserves a careful evaluation to sort out exactly what is contributing to the behaviors causing concern.

Attention Deficit Disorder (ADD) is the most commonly diagnosed behavioral disorder of childhood, affecting an estimated 3 - 5% of school aged children. It is diagnosed much more often in boys than in girls.

Most children with ADHD also have at least one other developmental or behavioral problem.