The classic image of a child with ADHD is practically a stock character: the spacey kid staring out the window, distracted by squirrels; the fidgeter who can't sit still, a leg rattling under the desk ...

For decades, Attention-Deficit/Hyperactivity Disorder (ADHD) has been all about behavior: kids who couldn’t sit still, adults who daydream, or anyone who acts ...

For years, stimulant medications for ADHD have been described as chemical accelerators, framed as drugs that rev up a sluggish brain. New imaging work turns that story on its head. Brain scans now ...