Whether the firing associations of grid cells depend on hippocampal inputs?

Noam Almog, Gilad Tocker, Tora Bonnevie, Edvard Moser, May-Britt Moser, Dori Derdikman. During hippocampal inactivation, grid cells maintain their synchrony, even when the grid pattern is lost. eLife 2019;8:e47147 DOI: 10.7554/eLife.47147

Abstract “The grid cell network in the medial entorhinal cortex (MEC) has been subject to thorough testing and analysis, and many theories for their formation have been suggested. To test some of these theories, we re-analyzed data from Bonnevie et al., 2013, in which the hippocampus was inactivated and grid cells were recorded in the rat MEC. We investigated whether the firing associations of grid cells depend on hippocampal inputs. Specifically, we examined temporal and spatial correlations in the firing times of simultaneously recorded grid cells before and during hippocampal inactivation. Our analysis revealed evidence of network coherence in grid cells even in the absence of hippocampal input to the MEC, both in regular grid cells and in those that became head-direction cells after hippocampal inactivation. This favors models, which suggest that phase
relations between grid cells in the MEC are dependent on intrinsic connectivity within the MEC.”

For further info, please read the paper Almog et al. 2019. 

Noam Almog, Gilad Tocker, Tora Bonnevie, Edvard Moser, May-Britt Moser, Dori Derdikman. During hippocampal inactivation, grid cells maintain their synchrony, even when the grid pattern is lost. eLife 2019;8:e47147 DOI: 10.7554/eLife.47147