You can knock a person out, or strike in such a way that the mobility is limited. I have never seen complete paralysis. And the only reason I believe in the latter is because it happen to me twice. Once suing my shiatsu class the lady working on me accidentally activated a point that took out most of my movement in my left arm. The instructor had to reverse it for me. I was quite amused by the fact i couldn't lift my arm above my waist

Of course it is especially if we are talking just causing a loss of feeling temporarily. An example of this is when you up to bat at the plate and don't hold the bat tight enough in your hands and make good contact with the ball, hitting it. Then you will feel the shock in your hands and wrists and forearms and they will go numb for a few seconds. Touching an electrified cattle fence is another example of what I am saying and how that will also cause a temporary loss of feeling in your arm or leg.

This is why when punching, striking, or kicking a well trained martial artist will aim for specific spots a lot of times rather than just at making contact on a general area. They also try to avoid making direct contact on their own body in some ways when blocking things as well. The wrist joint is a good example of what I am saying here and I have known some martial artists that have had to have surgery because they were not careful about blocking things on their wrist and having their wrist straight with their hand and forearm.

The neck and spine are especially vulnerable areas for serious or permanent injury which is why they don't allow any shots to the spine in structured fighting and why you don't see strikes and what not normally delivered to the neck in training and those strikes making any contact.

Nerve strikes or squeezes are so difficult to execute, that you would be better off making them a "minimal" part of your training at best. There are only a few situations where knowledge of pressure points (Atemi or Dim Mak) will help you, like in a close quarters struggle where a larger, stronger person is strangling you, and you have no other choice but to attempt a pressure point strike or squeeze to break the hold. Your best bet is to focus on striking and ground fighting. The pressure point techniques should be studied "after" you learn to strike and grapple effectively.

I was watching crouching tiger hidden dragon and I got to the scene where the jade fox took on the cop the girl and that one guy who can't really fight. I was blown away when the jade fox struck certain points on those guy who can't fight and had him frozen until lui mu bai came and reversed it. Is this an actual technique or was it just added for fun. I would love to study this and apply it in self defense