This definitely gives new meaning to rat race.
Viktor Toth, neuroengineer, trains rats to play Doom. In a Medium article, Toth explains how he's been training three rodents placed on top of a polystyrene ball tracked with motion sensors. The mice are suspended by harnesses while they ‘journey’ through the mazes of Doom II, presented before them on a PC monitor.
Viktor teaches the rats by way of positive reinforcement, feeding them through a tube of sugary water when they’re doing the right thing. Not only walking through the maps, the rats also learn to shoot up monsters. To do this, Viktor instructs them by activating the push-pull solenoid lifting the animals upwards, causing the head of the actuator to touch the button (effectively shooting down the monster), and finally rewarding the little critters with sugar water to reinforce the behavior.
Rats playing Doom II
Overview of the custom VR setup
Training rats to walk