A new study finds children with attention-deficit hyperactivity disorder have several brain regions that are slightly smaller than usual.
Researchers say it's more evidence that the disorder should be considered a neurological condition.
The study was published Wednesday in the journal Lancet Psychiatry and is the largest review of ADHD patients' brain scans ever conducted.
ADHD causes inattention, hyperactivity and impulsivity, although a given person may not show all those traits.
The scientists reviewed one scan per person and found no effect from ADHD medications.
Outside scientists say the findings are interesting, but there wasn't enough information to link the brain differences to behavioral problems seen in people with ADHD.
