Three win medicine Nobel for brain study

US-British scientist John O'Keefe and Norwegian husband and wife Edvard Moser and May-Britt Moser have won the Nobel Prize in medicine for discoveries of cells that constitute a positioning system in the brain.
The Nobel Assembly at the Karolinska institute says their discoveries have helped explain how the brain creates "a map of the space surrounding us and how we can navigate our way through a complex environment.