But not everyone experiences these symptoms, and so "by looking at concussion, it's not telling you anything about the brain or CTE", he added. "We can not overstate the absurdity of allowing 7-year-olds to receive 500 head impacts a season just because they happen to be getting exercise at the time".
Even as football programs from Pop Warner to the National Football League are adjusting their rules to reduce concussions, the findings suggest these efforts will not be enough to prevent long-term injury. The researchers found similar pathologies in both the mouse and human brains, regardless of the type of blast exposure they had experienced. People can be physically active, as long as they are not asking their brain to think.
The tau protein accumulation is one of the hallmarks of CTE; it gathers around small blood vessels in the brain, causing cell death, cognitive decline and dementia.
Tune in for "HealthLink on Air" this Sunday, January 21 at 6 a.m. and 9 p.m. on WRVO. "You don't have to be concussed to get Chronic Traumatic Encephalopathy and vice versa", said Dr. William Moss of the Lawrence Livermore Lab.
CTE can only be diagnosed by examining the brain after death.
"We've had an inkling that subconcussive hits - the ones that don't [show] neurological signs and symptoms - may be associated with CTE", Dr. "We were surprised that the brain pathology was unrelated to signs of concussion".
Many scientists believed concussions lead to the disease, but researchers at Boston University now say it's caused by repeated head trauma, with or without concussion.
"Children should not be exposed to repeated brain trauma", said Cantu, medical director of the Concussion Legacy Foundation and a long-time proponent of reducing young children's participation in football and other high-contact sports. The researchers hypothesized that damaged blood vessels leaking into brain tissue may cause early CTE. Lee Goldstein, an associate professor of psychiatry at the Boston University School of Medicine and the lead investigator on the study said, NPR reported. They were flanked by NFL Hall of Famers Nick Buoniconti and Harry Carson and Oakland Raiders legend Phil Villapiano.
"Football has been open season on your child's head from the time they're allowed to play", said Nowinski, who was an award-winning defensive tackle during his college days at Harvard.
"Head impact results in focal disruption" of capillaries, resulting in proteins leaking into the brain, he says. I've made the decision within my own family that my grandson will never play tackle football. But new research suggests that one does not necessarily need to obtain a concussion to develop the condition. But, he remains optimistic for the future of football.