The 2014 Nobel Prize in Physiology or Medicine

The Nobel Assembly at Karolinska Institutet has today decided to award the 2014 Nobel Prize in Physiology or Medicine with one half to John O'Keefe, and the other half jointly to May-Britt Moser and Edvard I. Moser for their discoveries of cells that constitute a positioning system in the brain. 

  

John O’Keefe
Studying rats in 1971, O'Keefe discovered that certain nerve cells in the hippocampus of the brain were activated when the rat was at a particular place in the environment. At other places, different nerve cells were active. He proposed the brain has "place cells" which allow rats to build an inner map of the environment.

May Britt and Edvard I. Moser
The Moser's work focused on a nearby structure in the brain, the entohinal cortex. They found that nerve cells in this portion of the brain were activated when rats passed certain locations in a maze. Together, these locations formed a hexagonal grid, with each "grid cell" as they called them, reacting in a unique spatial pattern. The grid cells form a coordinate system that allows for spatial navigation.

Grid cells and place cells form networks with each other and also with other cells that recognize the direction of the rat's head. This complex network is an inner GPS for the brain. However it's not just rats that have this positioning system. Humans, too, appear to have similar cells as those found in the rat brains.

Listen to their reactions:

May-Brit Moser:


John O'Keefe:


Edvard I. Moser:





Relevant Publications:
1. O'Keefe and Dostrovsky. "The hippocampus as a spatial map. Preliminary evidence from unit activity in the freely-moving rat brain." Brain Research, 1971, 34, 171.

2. O'Keefe, J. "Place units in the hippocampus of the freely moving rat." Experimental Neurology, 1976, 34, 78.

3. Fyhn et al. "Spatial representation in the entohinal cortex." Science, 2004, 305, 1258.

4. Hafting, et al. "Microstructure of spatial map in the entohinal cortex." Nature, 2005, 436, 801.

5. Sargolini et al. "Conjunctive representation of position, direction, and velocity in the entohinal cortex." Science, 2008, 312, 758.