Understanding ADHD -- the Basics
ADHD is a condition marked by persistent inattention, hyperactivity, and/or impulsivity. ADHD begins in childhood and often lasts into adulthood. About 30% to 50% of children with ADHD continue to have symptoms as adults.
Symptoms of ADHD can differ from person to person, but involve some combination of hyperactivity, impulsivity, and inattention. When activity levels are normal or low, it is usually called attention deficit disorder (ADD). The symptoms of hyperactivity and possibly impulsiveness appear to diminish with age.