The world is full of natural navigational (导航的) wonders. For example, pigeons can fly back home from thousands of miles away, and elephants can remember a watering hole that they once visited years ago.

Are humans any different? Apparently not. When we’re not using our phones to track our locations, we also have our own GPS systems in our brains, according to the 2014 winners of the Nobel Prize in physiology or medicine.

Norwegian scientist couple Edvard and May-Britt Moser won the prize jointly along with British-US scientist John O’Keefe. Their discoveries show us how the brain knows where we are and navigates from one place to another. They also help to explain why people with Alzheimer’s (a disease which is associated with memory loss) can’t recognize their surroundings.

It was all the way back in the 1970s when O’Keefe discovered that a specific set of cells in mice was always active when they entered a particular room. The cells, which O’Keefe called “place cells”, are located in a part of the brain called the hippocampus (海马体) and help form a map in the brain.

In 2005 the Mosers followed up the research and discovered what they call “grid cells”. They found that the brain creates a two-dimensional (二维的) grid of the world and the points on the grid are connected with people, places, and other sights, smells, and experiences.

You could say that the place cells mark Point A and Point B in the brain, and the grid cells help the brain get from Point A to Point B.

However, the research by the three Nobel Prize winners is still in its early stages. It’s unclear whether human brains are set up in the same way, according to Joshua Sanes, who is in charge of Harvard University’s Center for Brain Research.