to a

degenerative brain

known as Chronic Traumatic Encephalopathy, or

CTE. 

with CTE suffer from changes in their mood and

behavior that begin appearing in their

followed by problems

with thinking and memory that can, in some cases, even result in

dementia. The

show that at least among football players, between

. Sometimes that's

because it's hard to tell a concussion has

in the first

place. But it's also often due to

or a desire to keep

going 

the fact that something's wrong. This doesn't just

undermine

. Our brains aren't

invincible. They still need us to shield them from harm and help them

undo