White Matter (IMAGE) UT Southwestern Medical Center Caption Brain imaging shows yellow and reddish pixels representing areas where the functionality of white matter is associated with higher fitness levels. The images are based on cumulative data from patients in a study showing potential links between physical fitness and deterioration of white matter. Credit UT Southwestern Medical Center Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.