Healthy Children ages-8 to 17 can help scientists understand the mind. This 12-week outpatient research study at NIH in Bethesda, MD, investigates how the brain changes during computer-based training tasks and how breathing patterns and emotions are related in healthy children. Procedures include psychological interviews, a physical exam, lab work and brain scans. Compensation is provided. 301-827-1340, TTY: 1-866-411-1010.