Figure 3.

The spatial frequency of grid cells as a function of distance along the dorsoventral axis of the entorhinal cortex. According to Hafting et al. (2005), the intervertex distance varies from ≈35 cm in the most dorsal region to ≈8 m in more ventral regions (the most ventral region has not been recorded from). Granule cell recordings are from the dorsal hippocampus; based on anatomical results showing that this region receives input from only part of the entorhinal cortex, we estimate that the grid cells that provide input to granule cells have a spacing that varies from 35 cm to 1 m (two-headed arrow near bottom) (see Results).