With the right combination of the proverbial carrot and stick it turns out that people can train animals to do a shocking number of impressive tasks. Scientists, for example, have trained fish to drive cars on land. As well as teach monkeys how to play Pong. Now, Budapest-based machine-learning engineer Viktor Tóth has figured out a way to allow rats to play Doom II. Although they’re still just amateurs. (For now.)
Design Taxi picked up on Tóth’s experiment, which he says he undertook as a way to help automate the process of training animals in virtual reality (VR). Scientists use such experiments to study the “interplay of a wide variety of cognitive processes” in the brain, the engineer says. Tóth also notes in his detailed blog post that researchers are able to use setups like his Doom II rat rig to study a range of animal behaviors while simultaneously recording their neurobiological patterns.
In his blog post Tóth begins by describing how he built his setup. As the video above shows the rats play the video game by rotating a polystyrene ball with their feet. For the experiment, the engineer suspended the rats over the ball via a little harness. In front of the rats’ faces he placed a curved screen on which Doom II appeared.
![A rat using a rodent VR rig to play the video game Doom as a part of a recent lab experiment.](https://legendary-digital-network-assets.s3.amazonaws.com/wp-content/uploads/2022/01/12190744/Rat-Doom-feature-image-01072022.jpg)
To navigate the game, Tóth trained his rats using sugar water as a reward. As well as puffs of air to the face and/or rear as negative inputs. Placing the rat on the giant scrolling ball in front of the screen, the engineer then presented the rats with various levels from the video game; when the rats ran into walls, they received puffs of air. When they continued on through the maze-like levels, they received sugar water.
As for the results, Tóth says his three rats—Romero, Carmack, and Tom—could all run through the levels to some extent. Each of the three rats had different strengths and weaknesses, although it seems Romero was the best overall. Romero was so confident running in VR, in fact, that Tóth was even able to spend two sessions with him training how to shoot in-game. About a minute into the video above you can see the rat blowing away a baddie.
![A rat using a rodent VR rig to play the video game Doom as a part of a recent lab experiment.](https://legendary-digital-network-assets.s3.amazonaws.com/wp-content/uploads/2022/01/12190722/Doom-Rats-body-image-2.png)
Ultimately the engineer says he had “fun building a rodent VR rig and training rats to kinda play” Doom II. (Emphasis his.) He also says he was able to build his system for the “ridiculously cheap” price of $2,000. Although fully automating the process is apparently still a long way off. Which is cool with us, because fully automating anything that has to do with rats operating guns sounds like a bad Black Mirror episode.
Feature image: Viktor Tóth