In regards to this kind of project: PossessedHand: Techniques for controlling human hands using electrical muscles stimuli – Rekimoto Lab
I am wondering what the specifics are behind it? Would someone with more knowledge than me be able to explain this to a layman?
I'm no neurologist, but every muscle-motion is more or less triggered by electricity.
Usually the brain sends a signal to a muscle using the nervous system.
Humans exist of a lot of water, are electrically poorly insulated and the voltage found on nerves is pretty low.
That makes it possible to artificially create signals on a nerve. To a nerve it doesn't matter whether its controlled by brain or an external voltage on the right spots. It just sends the signal to the bodypart needed. Ditto for the muscle, it just reacts to the signal, whatever... is causing it.
Lots of accidents do happen because of this, should you for example grab a non insulated high voltage wire, muscles start reacting. Closing a hand can be done with much more force as opening it, the muscles simply are stronger. So, the grip gets stronger and even if you want to let go, nerves will keep sending a signal to the grabbing muscles.
People also "get thrown" into the air by high voltage shocks. That is when all their muscles are contracting at the same time. They literally jumped that high. Ordinary people can only coordinate a small percentage of their muscles to do something together. In reality, only muscles trained with the Fist of the North Star can control that much percent of their muscles. That's why he can destroy a freight train with his bare hands. BTW, that cartoon is also from Japan 
They (UofT) should really call their invention the fist of the north star to appeal to us "old-timers".