The Nobel Prize in medicine has been awarded to spouses May-Britt and Edvard Moser from Norway, 51 and 52 respectively, and John O’Keefe from New York, 75, for their work on understanding how the brain locates itself in space using an “inner GPS” made up of place cells and grid cells. O’Keefe will receive half of the award -- valued at $1.1 million in U.S. currency -- while the Mosers will split the other half.
The research spans more than four decades. O’Keefe, who teaches at University College London, discovered “place cells” in 1971 when he noticed that specific nerve cells in a rat’s hippocampus -- the area of the brain where that long-term memory and spatial navigation are located -- were activated when the animal entered a room. Another part of the brain became active with firing neurons when the rat entered a different room. According to NobelPrize.org, “O’Keefe discovered that certain nerve cells were activated when the animal assumed a particular place in the environment. He could demonstrate that these “place cells” were not merely registering visual input, but were building up an inner map of the environment…. Therefore, the memory of an environment can be stored as a specific combination of place cell activities in the hippocampus.”
Then, in 2005, the Mosers discovered a different type of nerve cell that they named a “grid cell” while working at the Norwegian University of Science and Technology in Trondheim. These cells create a coordinate system in the brain, similar to longitude and latitude lines on a map. This coordinate system allows "for precise positioning and pathfinding." The place cells and grid cells work together to navigate through space and determine position.
O’Keefe, told the BBC that he was in shock to receive the award, but his protégé Dr Colin Lever, was not surprised at all, telling the BBC that his mentor had “created a cognitive revolution” because the cells “form part of the spatiotemporal scaffold in our brains that supports our autobiographical memory.”
Rob Stein from NPR explained that this discovery has some far-reaching implications. "It really opened up whole new areas in how our brains work in creating things like memory and planning," he said.
The Nobel committee acknowledges that these cells are often affected in disorders that affect the brain, such as Alzheimer’s disease and dementia, which might be why people with these illnesses have a difficult time recognizing their surroundings. The committee said, "A better understanding of neural mechanisms underlying spatial memory is therefore important and the discoveries of place and grid cells have been a major leap forward to advance this endeavour."