You definitely do not want to be taking repetitive hard shots on a weekly basis, or even monthly. I'm doing my bachelors right now in brain trauma, concussions and PCS and the more I see the more I regret the way I did it myself. Your ego wont save you from the damage down the road. I don't care who you are, if you spar (hard) enough, often enough you'll take damage. The brain is not meant to take hits over and over again. Some might be able to tolerate it better, but it'll show years down the road.
I myself have never been KO'd, but looking back I've probably had minor concussions dozens of times between the ego slugfest wars in the gym, and getting socker kicked in the face, jumped, and hit in the head with a brick (seperate occasions), and more, in street scuffles. I wish I could go back and train smart, but I guess having a strong chin is a detriment sometimes when you rely on it. That's before my PCS started kicking in for real a few years ago.
This is not to say that you should be scared of getting hit, not at all. Taking damage once in a while in a fight is no big deal, but you should train smart and not get tagged hard in sparring. It's accumulation and no rest that's worst usually. 3-4 times a week with legitimate contact is way too much. That's the thing, it's very hard to compare sparring as well, because sparring at a boxing gym and sparring at an MT gym is like two different worlds. Recovery is also a HUGE factor, and stressors as well. You need to let the brain rest. When you get concussed basicly it's a cascade of certain biomarkers and inflammatory signalling, like various cytokines, in your brain. The more you rest your brains metabolism, the better.
If you're feeling off, take time off from sparring. Relax, and when you do spar do more shadow sparring, body sparring or very light sparring. It'll save your career, and save you a lot of trouble.
