The Nobel Assembly at Karolinska Institutet awarded the 2014 Nobel Prize in Physiology or Medicine to May-Britt Moser and Edvard I. Moser for their discovery of a "GPS system" in the brain.
The researchers discovered cells in the human brain that make it possible for us to orient ourselves, the Nobel Foundation reported.
In 1971, John O'Keefe noticed a type of nerve cell in a rat's hippocampus that was always activated when they were in a certain place in the room, and other nerves were activated when the rodent was in other places. The researcher concluded these cells created a "map" of the room.
Three decades later May-Britt and Edvard Moser discovered "grid cells" that generate the coordinating system and determine navigation. The researchers demonstrated "place cells "did not just simply register visual input, but were building "inner maps" of the environment. O'Keefe concluded the hippocampus generates numerous maps of the environment creating a memory that can be stored as a specific combination of place cells.
While mapping the rodents' brains as they moved around a room, May-Britt and Edvard Moser noticed a pattern of activity near the part of the brain known as the entorhinal cortex. In this region certain cells were activated when the rat passed multiple locations arranged in a hexagonal grid. The team believes the unique spatial pattern creates a coordination system allowing for spatial navigation. When coupled with cells that recognize the direction of the head and the borders of the room, the system forms circuits that act as an "inner GPS."
Recent studies involving brain imaging techniques and studies of patients undergoing neurosurgery have proved these grid cells also exist in humans. The findings could help researchers gain insight into degenerative diseases such as Alzheimer's, which often affect the hippocampus and entorhinal cortex in the early stages.
The findings represent a "paradigm shift" in our understanding of how cells work together to achieve complicated cognitive functions.
