Teen maturing brains become segregated into distinct network modules for greater efficiency. Researchers at the Perelman School of Medicine at the University of Pennsylvania uncovered this process in new research that maps the brain’s executive functions, which are key factors in a teen’s ability to control impulses, stay organized, and make decisions. As children age into adolescence and young adulthood, those ‘executive functions’ of the brain are key factors in determining outcomes, including educational success, drug use, and psychiatric illness. Now, researchers have mapped the changes in the network organization of the brain that underlie those improvements in executive function. The findings suggest that modular brain architecture is critical for the development of complex cognition and behavior. Researchers believe these insights could help identify biomarkers of abnormal brain development that could be used to predict a person’s risk for psychosis and major mood disorders.