LONDON -- Children with attention-deficit hyperactivity disorder have several brain regions that are slightly smaller than usual, more evidence that the disorder should be considered a neurological condition, a new study says. The study, the largest review of ADHD patients’ brain scans ever conducted, might also provide clues for developing new treatments. “If you know what region of the brain is involved in ADHD, you could possibly target that part with medication,” said Martine Hoogman of Radboud University in the Netherlands, the study’s lead author. ADHD causes inattention, hyperactivity and impulsivity, although a given person may not show all those traits. Hoogman and colleagues analyzed