I suffered a severe concussion in a bike accident in 1965. I've had a myriad of lesser concussions (14) over the 50 years since until a very minor one in 2001 put my brain past its ability to recover. I no longer have much of a functioning short term visual and auditory memory, I have slowed processing speed, and a serious problem with visual and auditory processing that makes it very easy to get visually or auditorily overwhelmed. I have been following concussion research for decades.