All your responses are greatly appreciated and thanks for the introductions!

As to confirm some of your speculations: I wouldn't label myself as ever being under the influence of TBI. I've only been self diagnosed of having a concussion as a kid due to the fact I was having a severe headache straight after a hard fall, though lasting only a couple of hours. Hence I believe it is a requirement to have symptoms of PCS before you're at risk of a TBI?

I read somewhere that a direct impact increases the odds of receiving a concussion by up to 50 times? Opposed to a indirect impact (rotation etc?). Anyways is there a difference in terms of shaking and rotating the head? Because yeah, I do kind of fear that my sudden rapid head rotation could cause tearing of axons? What mostly is bothering me is if we are able to produce the same force with our neck muscles as in a vehicle accident

Some claim you need to have the force equivalent of breaking/snapping your neck before a concussion can occur, this is with whiplash though.