Adnan Hirad (image) Carnegie Mellon University Share Print E-Mail Caption Adnan Hirad, an M.D./Ph.D. candidate at the University of Rochester's Medical Scientist Training Program and lead author of the study, said, "We hypothesized and found that the midbrain is a key structure that can serve as an index of injury in both clinically defined concussions and repetitive head hits. What we cataloged in our study are things that can't be observed simply by looking at or behaviorally testing a player, on or off the field. These are 'clinically silent' brain injuries." Credit Carnegie Mellon University Usage Restrictions None Share Print E-Mail 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.