Rats can use their imagination to move digital objects, reveals study

The power of imagination has been unique to humans, glorifying us as the most evolved species on earth. So far, only human brains have been known to have the ability to imagine a scenario and plan situations well ahead. But, scientists have recently discovered that animals, like humans, can imagine too. Controlling their thoughts and imagining a totally remote location is now found to be feasible for rats. A recent study conducted by Janelia and HHMI researchers has revealed that animals can control their brain activity and imagine virtual places and objects.

Neuroscientists Chongxi Lai and Albert Lee, along with their team, studied the brain activity of rats in controlling their spatial thoughts. Integrating virtual reality and brain-machine interface (BMI) they developed two stages of tasks for the rats in their study. They referred to the first task as "Jumper" as it was similar to the superpower of the protagonist in the movie "Jumper." Lee, who studies how brains can go back in time by revisiting memories and also jump ahead to imagine future scenarios, says that these processes, sometimes called “mental time travel,” are “part of what makes our inner mental lives quite rich and interesting."

In the first task, the animal was tested in a 360-degree immersive virtual reality environment through which it navigated by moving on a spherical treadmill. The rotation of the treadmill was converted into a visual update recording the neural activity signals from the animal's hippocampi (complex brain structures in the temporal lobe significant for spatial memory formation and retrieval). They were directed toward a reward (water) which was intended to be their goal location. The rats seemed to successfully navigate through the virtual world.   

In their second task, scientists tested whether the animal could move or direct an object to a random goal. Considering the resulting telekinesis type of actions in this task, researchers called it "Jedi" named after the knights of the "Star Wars" movie. Unlike the first task where the animal teleports to the goal, this task tested if an object can be teleported by the animal's imagination. While the rat stayed in a fixed location on the spherical treadmill, scientists studied its ability to access neural representations for places away from their location. The rats seemed to precisely control their own hippocampal activity and teleported the virtual objects to the goal location just like Yoda uses Force push on his enemies. 

In simple words, the rats just thought about remote places without actually going toward them and that was possible because their brains activated and sustained appropriate hippocampal representations of those remote places. "Overall, we believe our study is an exciting step forward in understanding cognitive maps and how they can be accessed through voluntary control. We look forward to seeing how this research develops and its potential applications in the future!" wrote Chongxi Lai on X.

The neuroscientists believe that the results of this study are the building blocks for understanding episodic memory recall, mental simulation/planning and imagination. Similar to the electrodes implanted in various brain parts that have aided in controlling robotic limbs, Lee and his colleagues hope that this research will be crucial for controlling advanced neural prosthetics with the help of signals from hippocampi. Speaking to ScienceNews about further developments in this study, Lee says "Humans can probably control their hippocampus for longer durations with a larger repertoire, and the concepts being encoded in the brain are probably much more complex."