Distinct speed dependence of entorhinal island and ocean cells, including respective grid cells

Entorhinal–hippocampal circuits in the mammalian brain are crucial for an animal’s spatial and episodic experience, but the neural basis for different spatial computations remain unknown. Medial entorhinal cortex layer II contains pyramidal island and stellate ocean cells. Here, we performed cell ty...

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Bibliographic Details
Main Authors: Sun, Chen, Kitamura, Takashi, Yamamoto, Jun, Martin, Jared, Kitch, Lacey J., Schnitzer, Mark J., Tonegawa, Susumu, Pignatelli di Spinazzola, Michele
Other Authors: Massachusetts Institute of Technology. Department of Biology
Format: Article
Language:en_US
Published: National Academy of Sciences (U.S.) 2016
Online Access:http://hdl.handle.net/1721.1/101119
https://orcid.org/0000-0002-2419-794X
https://orcid.org/0000-0003-2839-8228
Description
Summary:Entorhinal–hippocampal circuits in the mammalian brain are crucial for an animal’s spatial and episodic experience, but the neural basis for different spatial computations remain unknown. Medial entorhinal cortex layer II contains pyramidal island and stellate ocean cells. Here, we performed cell type-specific Ca[superscript 2+] imaging in freely exploring mice using cellular markers and a miniature head-mounted fluorescence microscope. We found that both oceans and islands contain grid cells in similar proportions, but island cell activity, including activity in a proportion of grid cells, is significantly more speed modulated than ocean cell activity. We speculate that this differential property reflects island cells’ and ocean cells’ contribution to different downstream functions: island cells may contribute more to spatial path integration, whereas ocean cells may facilitate contextual representation in downstream circuits.