2014′s Nobel Prize for Physiology or Medicine has been awarded to John O’Keefe, May-Britt Moser, and Edvard Moser for their discovery of the brain’s “inner GPS” system. The prize revolves around their discovery of place cells and grid cells — special neurons in the hippocampus and entorhinal cortex of animals (including humans, monkeys, and rats) that appear to create a cognitive map of every room or space that you’ve ever explored. As you move around a room or space, a very specific place cell fires — and when you visit the same place again in the future, the same place cell fires every time. The three researchers will share a $1.1 million prize.
Back in 1971, O’Keefe and Jonathan Dostrovsky discovered that the rat hippocampus had special place cells that, as their name suggests, are specifically involved with the rat’s current place. Prior to 1971 we already knew that the hippocampus was deeply involved with memory and learning, but the specificity of place cells and the cognitive spatial map they constructed was groundbreaking work. Later work has shown that there really are specific pyramidal neurons that fire in a certain pattern when an animal (rat, human, etc.) is in a specific place.