Alphaviper

Hey everyone! Me and my friend are currently developing (or should I say seeing if it is possible) a new kind of virtual reality headset. The system would have to cause temporary paralysis to the hand; and the process would have to be able to be stopped immediately on demand. This is a problem that has well and truly stumped me - biology (especially neuroscience) is not my area at all - engineering and physics is! I understand that there is a good chance there is no possible way of doing this - I may have to rethink it entirely... Thanks in advance!