title: Interaction of feedforward and feedback streams in visual cortex in a firing-rate model of columnar computations.
abstract: Visual sensory input stimuli are rapidly processed along bottom-up feedforward cortical streams. Beyond such driving streams neurons in higher areas provide information that is re-entered into the representations and responses at the earlier stages of processing. The precise mechanisms and underlying functionality of such associative feedforward/feedback interactions are not resolved. This work develops a neuronal circuit at a level mimicking cortical columns with response properties linked to single cell recordings. The proposed model constitutes a coarse-grained model with gradual firing-rate responses which accounts for physiological in vitro recordings from mammalian cortical cells. It is shown that the proposed population-based circuit with gradual firing-rate dynamics generates responses like those of detailed biophysically realistic multi-compartment spiking models. The results motivate using a coarse-grained mechanism for large-scale neural network modeling and simulations of visual cortical mechanisms. They further provide insights about how local recurrent loops change the gain of modulating feedback signals.
authors.affiliation: Institute for Neural Information Processing, University of Ulm, James-Franck-Ring, 89069 Ulm, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Brosch
authors.affiliation: Institute for Neural Information Processing, University of Ulm, James-Franck-Ring, 89069 Ulm, Germany. Electronic address: heiko.neumann@uni-ulm.de.
authors.forename: Heiko
authors.initials: H
authors.lastname: Neumann
mesh_terms: D000818:Animals; D025461:Feedback, Physiological / Q000502:physiology*; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology; D017966:Pyramidal Cells / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*
keywords: Binding; Feature integration; Feedback; Modulation; Neocortex; Pyramidal cells