UCLA researchers have found that space-mapping neurons — the GPS system in the brain — have a strong dependence on what is being looked at when triangulating location, a finding that resolves a neurological mystery that has vexed scientists for more than four decades.
This also expands on an earlier finding that neurons responsible for creating spatial maps react differently in virtual reality than they do in the real-world environments. Researchers again used rats in a virtual reality environment to test the long-debated theory of whether landmarks are necessary or whether that region of the brain is also counting steps or directional movement to determine location, said Mayank Mehta, a UCLA professor of neurology, physics and astronomy, and neurobiology in the UCLA College and the study’s senior author.
The study, which appears today in the peer-reviewed journal Cell, showed that many neurons were firing selectively only when rats were looking at certain landmarks on screens, either in the real or in the virtual reality environment.
“This part of the brain, the hippocampus, has neurons that fire in specific places. If I’m walking around a room, some neurons fire near the door, others around the middle of the room, and they all form a map of space in the brain,” said Mehta, who also is director of a W.M. Keck Foundation neurophysics center. “Where does this map come from? The classic idea was there are two possible mechanisms. One hypothesis is that neurons triangulate distances with respect to visual landmarks. However, it was…