Differences in Visual-Spatial Input May Underlie Different Compression Properties of Firing Fields for Grid Cell Modules in Medial Entorhinal Cortex

Firing fields of grid cells in medial entorhinal cortex show compression or expansion aftermanipulations of the location of environmental barriers. This compression or expansioncould be selective for individual grid cell modules with particular properties of spatial scaling.We present a model for differences in the response of modules to barrier location that arisefrom different mechanisms for the influence of visual features on the computation of locationthat drives grid cell firing patterns. These differences could arise from differences in theposition of visual features within the visual field. When location was computed from themovement of visual features on the ground plane (optic flow) in the ventral visual field, thisresulted in grid cell spatial firing that was not sensitive to barrier location in modules modeledwith small spacing between grid cell firing fields. In contrast, when location was computedfrom static visual features on walls of barriers, i.e. in the more dorsal visual field, thisresulted in grid cell spatial firing that compressed or expanded based on the barrier locationsin modules modeled with large spacing between grid cell firing fields. This indicatesthat different grid cell modules might have differential properties for computing locationbased on visual cues, or the spatial radius of sensitivity to visual cues might differ betweenmodules. PLOS Computational Biology , 01 Jan 0001, 01 Jan 0001,