Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, or excessive activity and impulsivity, which are otherwise not appropriate for a person's age.[1][2][3][4] Some individuals with ADHD also display difficulty regulating emotions or problems with executive function.[5][6][7][1] For a diagnosis, the symptoms should appear before a person is 12 years old, be present for more than six months, and cause problems in at least two settings (such as school, home, or recreational activities).[1][2] In children, problems paying attention may result in poor school performance.[8] Additionally, it is associated with other mental disorders and substance use disorders.[9] Although it causes impairment, particularly in modern society, many people with ADHD can have sustained attention for tasks they find interesting or rewarding (known as hyperfocus).[10][11]
