Cambridge scientists have shown that problems regulating emotions—which can manifest as depression, anxiety and explosive outbursts—may be a core symptom of attention deficit hyperactivity disorder (ADHD). In research published in Nature Mental Health, the team found that as many as one in two children with ADHD show signs of emotional dysregulation, and that Ritalin—the commonly-prescribed drug to help the condition—appears to be less effective at treating this symptom.