Rodent studies have demonstrated the existence of specialized neurons involved in spatial memory. These ‘grid cells’ represent where an animal is located within its environment, firing in patterns that show up as geometrically regular, triangular grids when plotted on a map of a navigated surface. Now for the first time, evidence for these cells has been found in humans. Moreover, those with the clearest signs of grid cells performed best in a virtual reality spatial memory task, suggesting that the grid cells help us to remember the locations of objects. These cells, located particularly in the entorhinal cortex, are also critical for autobiographical memory, and are amongst the first to be affected by Alzheimer's disease, perhaps explaining why getting lost is one of the most common early symptoms.
Connection between navigation, object location, & autobiographical memory
Reference
Doeller, C. F., Barry, C., & Burgess, N. (2010). Evidence for grid cells in a human memory network. Nature, 463(7281), 657-661. Retrieved from http://dx.doi.org/10.1038/nature08704
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