This is one use of VR that you might think was an elaborate hoax or something from a novel. The idea is to let man and animals, a rat in this case, operate on more equal terms.

Researchers at University College London (UCL) and the University of Barcelona have invented "beaming". The term being an oblique reference to the Star Trek transporter mechanism, although in this case beaming goes beyond the basic relocation idea.

What we have is a VR way to change a man into a rat and vice versa. The rat interacts with a robot rat controlled by the human and the human interacts with an avatar controlled by the rat. The interaction is two-way and both parties have to learn how to behave in their new environments.

In the initial experiments the two animals were 12km apart - the human on the Barcelona campus and the  rat in an animal welfare center.

The rat is monitored using video tracking and its movements scaled up to an avatar in a room sized VR arena. The rat's overall position and its head position were mapped to the human avatar. The human was tracked in the same way and the results used to control the position of a small, round, robot

In the interaction experiments the rat was first trained to follow the robot. The humans were trained initially so that they saw both the VR environment and the real rat occasionally in an effort to convince them that the avatar was a real living animal.

After this training, the human and rat played a game. The room had posters on the wall -  a computer mouse, the face of Mickey Mouse, a poster from the movie Ratatouille, a picture of a real rat with a piece of cheese. The game was to move both avatars to be in front of a particular poster and within a given distance. It they got close in front of the wrong poster then the rat won and received a reward.

A second game with the same rules again involved the rat and the human but this time the human was told that it was another human playing.

A statistical analysis of the position data suggest that the rat actually engaged with the human in playing the game and the humans' behavior changed when they thought the opponent was another human rather than the rat.

You can see it in action in the video:

So what is it all for?

A good question, but you can appreciate the fascination of the idea of interspecies interaction without the barriers of physical appearance.  The authors of the research paper claim that the experiment was as much about showing the technique was workable as much as anything else. Obviously, behavioral scientists could make use of it to study animal behavior by observing it "mapped" onto a human avatar, but what if the general media started to use it? Would humans understand animals any better expressed in a human form? Would their interactions with them change as a result?