May-Britt Moser and Edvard Moser and colleagues discovered grid cells, specialized types of neurons that respond to specific locations in space. They are main components of the brain's GPS.
Order of authorship in the original publication: Hafting, Fyhn, Moden, Moser, Moser.

In 2014 May-Britt Moser and Edvard Moser shared the Nobel Prize in Physiology or Medicine with John O'Keefe “for their discoveries of cells that constitute a positioning system in the brain.”