Journal ArticleDOI
Recurrent inhibitory circuitry as a mechanism for grid formation
Jonathan J. Couey,Aree Witoelar,Sheng-Jia Zhang,Kang Zheng,Jing Ye,Benjamin Dunn,Rafal Czajkowski,May-Britt Moser,Edvard I. Moser,Yasser Roudi,Menno P. Witter +10 more
TLDR
It is demonstrated that stellate cells, the principal cell type in the layer II grid network, are mainly interconnected via inhibitory interneurons, and that stable grid firing can emerge from a simple recurrent inhibitory network.Abstract:
Grid cells in layer II of the medial entorhinal cortex form a principal component of the mammalian neural representation of space. The firing pattern of a single grid cell has been hypothesized to be generated through attractor dynamics in a network with a specific local connectivity including both excitatory and inhibitory connections. However, experimental evidence supporting the presence of such connectivity among grid cells in layer II is limited. Here we report recordings from more than 600 neuron pairs in rat entorhinal slices, demonstrating that stellate cells, the principal cell type in the layer II grid network, are mainly interconnected via inhibitory interneurons. Using a model attractor network, we demonstrate that stable grid firing can emerge from a simple recurrent inhibitory network. Our findings thus suggest that the observed inhibitory microcircuitry between stellate cells is sufficient to generate grid-cell firing patterns in layer II of the medial entorhinal cortex.read more
Citations
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Journal ArticleDOI
GABAergic Interneurons in the Neocortex: From Cellular Properties to Circuits
TL;DR: Current understanding of neocortical interneuron diversity and the properties that distinguish cell types are reviewed and it is illustrated how recent advances in the field have shed light onto the mechanisms by which GABAergic inhibition contributes to network operations.
Journal ArticleDOI
Perineuronal nets stabilize the grid cell network
Ane Charlotte Christensen,Kristian Kinden Lensjø,Mikkel Elle Lepperød,Svenn-Arne Dragly,Hallvard Sutterud,Jan Sigurd Blackstad,Marianne Fyhn,Torkel Hafting +7 more
TL;DR: It is shown that removal of perineuronal nets leads to lower inhibitory spiking activity, and reduces grid cells’ ability to create stable representations of a novel environment, and that PNN removal in entorhinal cortex distorted spatial representations in downstream hippocampal neurons.
Journal ArticleDOI
Fast-spiking, parvalbumin+ GABAergic interneurons: From cellular design to microcircuit function
Hua Hu,Jian Gan,Peter Jonas +2 more
TL;DR: Not only are PV+ interneurons involved in basic microcircuit functions, but they also play a role in complex network operations, including expansion of dynamic activity range, pattern separation, modulation of place and grid field shapes, phase precession, and gain modulation of sensory responses.
Journal ArticleDOI
Speed cells in the medial entorhinal cortex
TL;DR: It is shown that running speed is represented in the firing rate of a ubiquitous but functionally dedicated population of entorhinal neurons distinct from other cell populations of the local circuit, such as grid, head-direction and border cells.
Journal ArticleDOI
Spatial Representation in the Hippocampal Formation: A History
TL;DR: It is now possible to investigate how specialized cell types of hippocampal–entorhinal systems work together, and spatial mapping may become one of the first cognitive functions to be understood in mechanistic detail.
References
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