ADHD: A Defintion


Attention-Deficit Hyperactivity Disorder (ADHD or AD/HD or ADD) is a neurobehavioral|LS|1|RS| developmental disorder.|LS|2|RS| It is primarily characterized by "the co-existence of attentional problems and hyperactivity, with each behavior occurring infrequently alone" and symptoms starting before seven years of age.|LS|3|RS|