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bioRxiv · 10.1101/186007

Inter-areal balanced amplification enhances signal propagation in a large-scale circuit model of the primate cortex

Abstract

Reliable signal transmission represents a fundamental challenge for cortical systems, which display a wide range of weights of feedforward and feedback connections among heterogeneous areas. We re-examine the question of signal transmission across the cortex in network models based on recently available mesoscopic, directed- and weighted-inter-areal connectivity data of the macaque cortex. Our findings reveal that, in contrast to feed-forward propagation models, the presence of long-range excitatory feedback projections could compromise stable signal propagation. Using population rate models as well as a spiking network model, we find that effective signal propagation can be accomplished by balanced amplification across cortical areas while ensuring dynamical stability. Moreover, the activation of prefrontal cortex in our model requires the input strength to exceed a threshold, in support of the ignition model of conscious processing, demonstrating our model as an anatomically-realistic platform for investigations of the global primate cortex dynamics.

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Joglekar, M. R., Mejias, J. F., Yang, G. R., Wang, X.-J.. 2017-09-07. Inter-areal balanced amplification enhances signal propagation in a large-scale circuit model of the primate cortex. https://doi.org/10.1101/186007

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