Narrator:        This is Science Today. In a groundbreaking study, UCLA researchers have used a brain-imaging tool to look at abnormal brain proteins in retired NFL players who have suffered one or more concussions on the field.

Small:            This is the first time we've been able to image in living football players, protein deposits that we've observed in people with Alzheimer's disease. 

Narrator:        Study leader Dr. Gary Small explains that previously, these tau protein deposits could only be established by an autopsy. But they used a chemical marker that can bind to these proteins and cause the deposits to light up in PET scans.

Small:             Although this is a small, preliminary study, if the findings hold up, we may be able to detect these early signs of Alzheimer's in head trauma victims before symptoms become severe.

Narrator:        The Centers for Disease Control and Prevention estimates that millions of sports-related concussions and mild traumatic brain injuries occur each year. For Science Today, I'm Larissa Branin.