Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder defined by impairing levels of inattention, disorganization and/or hyperactivity-impulsivity
Inattention and disorganization is the inability to stay on task, lack of listening skills, and losing materials necessary for tasks, at levels that are inconsistent with age or developmental level
Hyperactivity-impulsivity involve overactivity, fidgeting, inability to stay seated, intruding into other people’s activities and inability to wait; symptoms that are excessive for age or developmental level
Frequently overlaps with externalizing disorders (eg oppositional defiant disorder, conduct disorder) during childhood, and often persists into adulthood, with resultant impairments of social, academic and occupational functioning
