However, I've convinced myself that it may be detrimental to my long term cognitive abilities. Do any HN martial arts participants have any insight into this? Can one really expect to repeatedly get hit in the head and not pay for it, long term?
The serious answer... I've been studying Kenpo, one of the most violent martial arts, for the past 2.5 years. Usually when you are sparring, there is a mutual level of respect. You aren't out there trying to kill each other, its not like an MMA fight on TV. It is also not like boxing, you are standing 2 feet away from each other just trading blows.
Most studios will let you sit and watch a class before signing up. If it looks like there are a couple of tough guys trying to take people's heads off, just walk away, it is not a good studio. Those types of lunk heads never last more than a few weeks in a real studio because after sparring with a more experienced student, they won't want to come back.
People get hurt, but it has never been from a shot to the head. In the vast majority of cases, the injuries are been self inflicted. A broken finger, a smashed shin, a broken toe, usually the result of poor technique due to frustration.
"Well we don't know without analysis... Health concerns are mostly long-term, and there's no definitive answer on how much getting hit in the head is required for permanent brain damage. Re: concentration, I'm even less convinced; maybe it's not the getting hit that is bad for concentration but the switch between mental/physical activity. Or maybe concentration improves with more adrenaline."
"Yes, for boxing champions, but even there it's hard to say what is caused by the boxing and what is caused by genetic factors. People often say 'look at Ali!' but there's no way to tell if it's really because of the boxing. But more importantly, note that I said 'how much getting hit in the head is required'. See e.g.
http://www.sciencedaily.com/releases/2007/05/070502093035.ht....
http://www.bmj.com/content/335/7624/809.full
Both from 2007. First one says that amateur boxers do get brain damage, second one says they don't. (there are the top google hits, I looked into this deeper about 5 years ago; at that time there was very little research done, let alone consensus.)
Point being, the question is: does getting hit in the head pose linear risks/ I.e, simplified, do a number of cells die for each punch or kick to the head? Or does it require a certain threshold of damage for there to be any cognitive effects?
I don't compete in any sport but I've trained plenty of full contact sports over the last 10 or 15 years. I've been punched and kicked in the face a lot, with and without gloves, been knocked out briefly once, been choked out several times. Still my head/brain has taken nowhere near the amount of punishment a pro or even good amateur fighter gets; my brains gets plenty of time between trainings to recover. I can never know for sure if my training has caused brain damage, and if it did, in what form that will manifest itself (or has already, maybe), but I don't have reasons to believe it affected my cognitive functions. Maybe it did and the damage caused decreased intelligence, making me believe that it didn't :)"
Or just try starting with Bjj or something where there's no strikes to the head if you're worried.
Also if you don't competet and only do light sparing you won't get hit hard in the head.
So go to you local gym and have fun!