Neuroscientist Steven Novella blogs about a recent study on the brain cells involved in navigation through space. Previous research discovered the existence of place cells, which the brain uses to track locations; the new study discovered grid cells, which the brain uses to direct motion through an environment. Evidently, the brain uses a hex map to direct movement:
A specific place cell will fire when we are in a specific location. Different patterns of place cells firing represent different locations.
These place cells are found in the hippocampus, specifically area CA1. O’Keefe also found that the place cells have memory function, and are therefore critical to our ability to remember specific locations.
Moser and Moser extended this work by finding grid cells in the entorhinal cortex. This area connects heavily with CA1, and contains cells that behave like the place cells. However, the grid cells are arranged in a hexagonal grid [emphasis added], and they fire in sequence as rats move through their environments. The grid cells therefore seem to be a literal map of the environment, and track our movement through the environment, while the place cells tell us where we are.