Well, guess it's already my turn to bring this thread back from the dead, yet again! My concern this time revolves around whipping your head back an forth instead of turning it side to side. So in a way, I'm worrying about the opposite, at least in form of directions. So if for example you stand still, look up in the air quickly followed by a quick look back to the ground, would this up an down movement with the body standing still, cause cumulative injury resulting in sub concussive blows? Or does it take a bit of force to cause that too? I mean in headbanging you use the body to create extra force of some sort, what if you're simply standing still and only using your head to look up and down really quickly. If it were to cause cumulative injury sometimes by doing this, wouldn't it take hundreds to thousands of times in a relative short time span for problems to arise? I mean it's pretty much impossible to give a full blown concussion from simply looking up in the sky fast or down at the ground fast, right? Think about if were scared for example, if a ball is over our head about to hit us, I guess our body unconsciously does a fast movement to look up with out heads. I have OCD, so I easily get scared by any fast movement of my head, so I have to do it consciously several times after with even faster movement, to ensure that no symptoms other than anxiety appears. So I'm just worried if I've made it all worse and causing countless of sub concussive blows.

To summarize, I remember I got told on here that fast backward or forward motion with the head could cause cumulative injury tearing axons, but isn't that only with headbanging type of behavior where their whole upper body is in motion to produce the required force? What if you only use your head fast up and down, similar to turning your head side to side, the only difference is the linear and rotational factors here. Whipping up/down is linear, turning side to side is rotational, is there any difference in terms of potential dangers of the two? Am I gonna be okay from these couple of super fast up/down head movements with the neck?