Eleven percent of kids ages 4-17 suffer from attention deficit hyperactivity disorder. This hour, we’ll talk about the root causes of A.D.H.D., the limits of Adderall and Ritalin, and how simple solutions can sometimes be the most effective with Dr. Richard Friedman, professor of clinical psychiatry and the director of the psychopharmacology clinic at Weill Cornell Medical College. Dr. Friedman wrote about natural fixes for A.D.H.D. in a recent issue of The New York Times.