Speed cells in the medial entorhinal cortex

EMILIO KROPFF; ERIC CARMICHAEL; MAY-BRITT MOSER; EDVARD I MOSER

NATURE

NATURE PUBLISHING GROUP

Lugar: Londres; Año: 2015 vol. 523 p. 419 - 424

0028-0836

Grid cells in the medial entorhinal cortex (MEC) have spatial firing fields that repeat periodically in a hexagonal pattern. When animals move, activity is translated between grid cells in accordance with the displacement in the environment. For such translation to occur, grid cells must have continuous access to information about instantaneous running speed. However, a powerful entorhinal speed signal has not been identified. Here we show that running speed is represented in the firing rate of a ubiquitous but functionally dedicated population of MEC neurons distinct from other MEC populations, such as grid, head direction and border cells. This entorhinal cell type is characterized by a context-invariant positive, linear response to running speed. Speed cells and grid cells share a similar prospective bias of ~50 to 80 ms. The observations point to speed cells as a key component of the dynamic representation of self-location in the MEC.