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bioRxiv · 10.1101/2020.04.21.051268

Modeling robust and efficient coding in the mouse primary visual cortex using computational perturbations

Abstract

Investigating how visual inputs are encoded in visual cortex is important for elucidating the roles of cell populations in circuit computations. We here use a recently developed, large-scale model of mouse primary visual cortex (V1) and perturb both single neurons as well as functional- and cell-type defined population of neurons to mimic equivalent optogenetic perturbations. First, perturbations were performed to study the functional roles of layer 2/3 excitatory neurons in inter-laminar interactions. We observed activity changes consistent with the canonical cortical model (Douglas and Martin 1991). Second, single neuron perturbations in layer 2/3 revealed a center-surround inhibition-dominated effect, consistent with recent experiments. Finally, perturbations of multiple excitatory layer 2/3 neurons during visual stimuli of varying contrasts indicated that the V1 model has both efficient and robust coding features. The circuit transitions from predominantly broad like-to-like inhibition at high contrasts to predominantly specific like-to-like excitation at low contrasts. These in silico results demonstrate how the circuit can shift from redundancy reduction to robust codes as a function of stimulus contrast.

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Cai, B., Billeh, Y. N., Chettih, S. N., Harvey, C., Koch, C., Arkhipov, A., Mihalas, S.. 2020-04-23. Modeling robust and efficient coding in the mouse primary visual cortex using computational perturbations. https://doi.org/10.1101/2020.04.21.051268

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