Researchers from the Korea Advanced Institute of Science and Technology created steerable cyborg mice, and holy hell is this experiment giving me the creeps. 

The researchers hacked the parts of the mice's brains that crave and chase objects by stimulating it with a fiber optic thread. This process, called optogenetics, turns neurons on and off with bursts of light. Turning the light on made the mouse crave a ball that was hanging in front of its face. The researchers were able to make the mouse walk by pointing the ball in a particular direction and stimulating the object-craving part of its brain.

The researchers tested the robo-mouse by dropping it into a maze filled with distractions, including a female mouse, food, rough terrain, and a narrow bridge. Without the light stimulation, it meandered. With the light stimulation, and a human steering the way with the ball, the mouse cut a direct path to the end of the maze.

The researchers' work was published in the March issue of Nature Neuroscience.