UCLA researcher uses virtual reality to understand how animals perceive space
When healthy, we don’t appreciate this gift. However, spatial memory is one of the first functions to deteriorate in several neurological conditions including epilepsy and Alzheimer’s disease. That is why UCLA neurophysicist Mayank Mehta devotes his career to studying how the brain, and especially the cells in the region called the hippocampus, learns to create our perception of space and time.
As Mehta notes, all animals (including humans) “agree 100 percent on concepts of abstract space and time.” And all animals calculate where they are in space in the same way or else they would bump into each other and the objects around them.
Such universal perception of space-time is possible because a set of hippocampal neurons, called “place cells,” fire in an orderly fashion as any animal navigates a jungle, a living room or a maze, laying down a map of space-time without even trying.
How do they turn light, sounds, smells, for example, into a universal perception of space and time?
To resolve this question, Mehta concluded, one would need to tease apart the different sensory stimuli that constitute space-time. This is impossible to do in the real world, but it can be accomplished readily in the virtual world.
In one experiment, the researchers compared the rats’ ability to locate rewards hidden in a real world maze — where rats can use sights, sounds and odors to navigate — with their ability to locate rewards in a virtual maze, where they’re limited to using only visual cues.
First though, an interdisciplinary team that included UCLA students in neuroscience, psychology, computer science, engineering and physics had to build the virtual apparatus from scratch. They designed the hardware, including a ball-shaped treadmill, and trained the rats to become comfortable in virtual reality and to play virtual games.
The findings were surprising. The rats in the virtual maze found hidden rewards as skillfully as rats in a real maze. Rats, it turned out, can see quite well.
These studies demonstrate that the brain needs inputs from multiple sensory factors to construct a working spatial map, Mehta said. If the vision says you are moving in space, but the sounds and smells tell otherwise, as is the case in virtual reality, the neural activity becomes very strange.
See the full story here: http://newsroom.ucla.edu/stories/ucla-researcher-uses-virtual-reality-to-understand-how-animals-perceive-space