A chronic disorder whose symptoms include failure to develop normal social relations with other people, impaired development of communicative ability, lack of imaginative ability, and repetitive, stereotypical movements.
The principal characteristics of ADHD are inattention , hyperactivity , and impulsivity . These symptoms appear early in a child's life.
There are three patterns of behavior that indicate ADHD. People with ADHD may show several signs of being consistently inattentive. They may have a pattern of being hyperactive and impulsive. Or, they may show all three types of behavior.
NIMH Child Psychiatry Branch studied 152 boys and girls with ADHD, matched with 139 age- and gender-matched controls without ADHD. The children were scanned at least twice, some as many as four times over a decade. As a group, the ADHD children showed 3-4 percent smaller brain volumes in all regions—the frontal lobes, temporal gray matter, caudate nucleus, and cerebellum.
A category of chemicals released by certain white blood cells when they detect the presence of an invading microorganism; causes other white blood cells to proliferate and mount an attack against the invader.