Berlin 2012 – wissenschaftliches Programm

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DY: Fachverband Dynamik und Statistische Physik

DY 22: Posters I

DY 22.52: Poster

Mittwoch, 28. März 2012, 17:00–19:00, Poster A

Active self-organization of disordered arrangements of orientation preference in cortical networks — •Juan Daniel Florez Weidinger, Wolfgang Keil, and Fred Wolf — Max Planck Institute for Dynamics and Self-organization and Bernstein Center for Computational Neuroscience, Gottingen,

Many response characteristics of neurons in the brain, including orientation tuning in the primary visual cortex, are believed to arise by dynamical self-organization. The spatial arrangements of tuning properties across the cortex show fundamental interspecies differences. While in primates and carnivores orientation preference form organized orientation maps, in rodents it appears to be randomly distributed. It has been shown that orientation maps in different species realize a common design which can be quantitatively explained by dynamical self-organization. It remains unclear whether a similar approach can also explain rodent functional organization. Here we present an analytically tractable symmetry-based model of the activity-dependent development of orientation selectivity that can describe both types of organization. In the model neurons interact in a distance dependent manner both with isotropic and with orientation selective inhibition and excitation. By symmetry this model has a large set of exact map solutions. Analytically examining their stability, we find that with strong short-range inhibition all map solutions become unstable. We show numerically that in this regime, disordered arrangements become the attractor state of the network.

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