December 13, 2012
When processing what the eyes see, the brains of primates don’t use square grids, but instead use triangles, research from Yerkes neuroscientist Beth Buffalo’s lab suggests.
She and graduate student Nathan Killian recently published (in Nature) their description of grid cells, neurons in the entorhinal cortex that fire when the eyes focus on particular locations.
Their findings broaden our understanding of how visual information makes its way into memory. It also helps us grasp why deterioration of the entorhinal cortex, a region of the brain often affected early by Alzheimer’s disease, produces disorientation.
The Web site RedOrbit has an extended interview with Buffalo. An excerpt:
The amazing thing about grid cells is that the multiple place fields are in precise geometric relation to each other and form a tessellated array of equilateral triangles, a ‘grid’ that tiles the entire environment. A spatial autocorrelation of the grid field map produces a hexagonal structure, with 60º rotational symmetry. In 2008, grid cells were identified in mice, in bats in 2011, and now our work has shown that grid cells are also present in the primate brain.
Please read the whole thing!