First recognized in rats in 2005, humans may also owe their sense of direction in part to grid cells—neurons that...

First recognized in rats in 2005, humans may also owe their sense of direction in part to grid cells—neurons that fire in a triangular pattern and help keep track of navigational cues—according to a recently published study. 
Recording the neuronal activities of people asked to locate invisible objects in a virtual environment, researchers at Drexel University observed grid-like firing in two regions of the brain, providing the most concrete evidence yet for the existence of grid cell activity in humans.

Source: http://www.the-scientist.com/?articles.view/articleNo/36881/title/Mapping-Humans--Mental-GPS/