It was discovered by a pathologist named Bennet Omalu and brought to the public eye when he published the first documented evidence of the disease after a thorough study of former Pittsburgh Steeler, Mike Webster.
And later that month, a federal appeals court ruled league administrators ignored evidence of a retired player's CTE when considering his eligibility for disability payments. This is because those sports - football, soccer, hockey, and boxing in particular - are increasingly linked with a condition known as chronic traumatic encephalopathy (CTE). The level, play time and positions of the football players whose brains were used in the study varied, and the numbers are staggering.
Former Tennessee Titans tight end Frank Wycheck, now a color commentator on Titans broadcasts and co-host of a daily talk show on 104.5 The Zone, worries that concussions during his nine-year career have left him with chronic traumatic encephalopathy. 87% of the brains were diagnosed with CTE, and 99% of the brains of the former National Football League (NFL) players showed signs of CTE, which can only be diagnosed after death.
Dr. Munro Cullum, a neuropsychologist at UT Southwestern Medical Center in Dallas, emphasized that the report is based on a selective sample of men who were not necessarily representative of all football players.
The NFL responded to the new research in a statement reading in part, "The medical and scientific communities will benefit from this publication and the NFL will continue to work with a wide range of experts to improve the health of current and former NFL athletes".
Anthony Tall is a sports agent with Aspire Sports Agency.
The average age of death among all players studied was 66. "I think they're very anxious about it".
"Certainly, a number of things that I've noticed over the years that have led me to sort it out", he said. All the participants were exposed to a relatively similar type of repetitive head trauma while playing the same sport. However, the longer the players were involved in the game and higher the level of performance, the more likely they were to have developed more severe cases of CTE.
The JAMA study is the largest of its kind and all of those studied were required to have football as their primary exposure to head trauma.
CTE is still not completely understood by health professionals, but other possible signs and symptoms may include depression or apathy, substance abuse, suicidal thoughts or behavior, irritability, aggression, trouble swallowing, vision and focusing problems, and trouble with sense of smell, according to Mayo Clinic. "In Alzheimer's disease, there are tau protein deposits in certain areas of the brain than are different than what you see in CTE".