The release of the autopsy results for former New England Patriot Aaron Hernandez has renewed questions about CTE-related deaths and safety in football, leading to research on the disease and changes in the sport.
Chronic Traumatic Encephalopathy is a neurodegenerative disease that scientists believe is caused by repeated brain trauma. The trauma causes tau proteins to form depositions in the brain, which spread and kill brain cells.
Joel Morgenlander, a professor of neurology and orthopaedic surgery at Duke University, said there is no definitive answer to what causes CTE.
“Defining the disease is still a process,” he said.