Researchers from the Cavil Institute at the Norwegian University of Science and Technology (NTNU) have uncovered a surprising revelation regarding the functioning of “grid cells” – neurons essential in helping the brain establish a mental map of its surroundings. Contrary to previous belief, these cells not only track location but also engage in a predictive scanning process of the space ahead.
Discovered in 2005 by May-Britt and Edvard Moser, grid cells are integral to the brain’s navigation system, aiding in spatial orientation and movement. However, a recent study has revealed that these neurons are more dynamic than originally thought.
Scientists have found that grid cells exhibit rhythmic “sweeps” – rapid scanning movements of 30 degrees to the right and then to the left, occurring ten times per second. These movements resemble antennas probing the environment ahead, creating a detailed and adaptable mental map of the surroundings.
This breakthrough was made possible by utilizing state-of-the-art technology – Neuropixels 2.0 neuropixel sensors capable of capturing thousands of neural interactions with millisecond precision. These sensors enabled researchers to detect subtle changes in grid cell activity that were previously overlooked.
A team of scientists, including Abraham Zeljko Vollan, Rich Gardner, May-Britt Moser, and Edvard Moser, decoded brain data gathered during rodent navigation experiments. They observed that the mental map generated by the brain does not perfectly align with the actual location of the animal. Instead, grid cells continuously propagate waves of activity to adjacent areas of the map, anticipating future spatial information.
This mechanism bears resemblance to the echolocation principles seen in bats or the antenna functionality in insects, allowing the brain to preemptively evaluate the surroundings for efficient navigation.
The study also revealed that these scanning movements occur even during sleep, particularly during the rapid eye movement (REM) phase when the brain processes information. This suggests that grid cells not only operate in real-time but also contribute to memory formation and the creation of new mental maps.
Published in the journal Nature on February 3, 2025, this discovery has the potential to revolutionize current understanding of how the brain controls navigation. Scientists speculate that a similar mechanism may exist in humans, with these “sweeps” potentially linked to eye movements and attention focus.
Researchers at the Cavil Institute are committed to further exploring this area to gain a deeper understanding of the brain’s navigation system and uncover any additional hidden mechanisms at play.