Modularity and robustness of frontal cortical networks.

Neural activity underlying short-term memory is maintained by interconnected networks of brain regions. It remains unknown how brain regions interact to maintain persistent activity while exhibiting robustness to corrupt information in parts of the network. We simultaneously measured activity in large neuronal populations across mouse frontal hemispheres to probe interactions between brain regions. Activity across hemispheres was coordinated to maintain coherent short-term memory. Across mice, we uncovered individual variability in the organization of frontal cortical networks. A modular organization was required for the robustness of persistent activity to perturbations: each hemisphere retained persistent activity during perturbations of the other hemisphere, thus preventing local perturbations from spreading. A dynamic gating mechanism allowed hemispheres to coordinate coherent information while gating out corrupt information. Our results show that robust short-term memory is mediated by redundant modular representations across brain regions. Redundant modular representations naturally emerge in neural network models that learned robust dynamics. [Display omitted] • Correlated and redundant representations of choice across frontal cortical networks • Individual variability shows that modular organization is required for robustness • Dynamic gating allows communication and compartmentalization between brain regions • Redundant modular representations naturally emerge in robust network models Examining interactions between brain regions across mouse frontal hemispheres uncovers individual variability in the organization of networks with redundant modular representations that maintain short-term memory and naturally emerge in robust network models. [ABSTRACT FROM AUTHOR]