Attention-deficit/hyperactivity disorder (ADHD) is often talked about as if it were a single condition. But anyone who works with children with ADHD-or raises one-knows that symptoms can look very different from one child to another. A new brain imaging study now provides scientific evidence for this everyday observation, showing that ADHD is not one-size-fits-all at the level of brain structure. In a recent study published in General Psychiatry, researchers from Shandong First Medical University in China analysed brain scans from children and adolescents with ADHD to better understand how changes in the brain relate to different behavioural symptoms.