This is a mind-controlled artificial hand. There is a video in the link that shows the movement.
This is impressive and a great start to more functionality. With better actuators one might be able to play the piano with it!

97 to 98 percent accuracy, they say. But secretly, the remaining 2-3% of the time, it tries to pick your nose… old habits die hard…

Mind-Controlled Prosthetic Hands Grasp New Feats Users can move individual fingers simply by thinking about it