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Temporal decorrelation of collective oscillations in neural networks with local inhibition and long-range excitation

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 نشر من قبل Demian Battaglia
 تاريخ النشر 2007
  مجال البحث علم الأحياء فيزياء
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We consider two neuronal networks coupled by long-range excitatory interactions. Oscillations in the gamma frequency band are generated within each network by local inhibition. When long-range excitation is weak, these oscillations phase-lock with a phase-shift dependent on the strength of local inhibition. Increasing the strength of long-range excitation induces a transition to chaos via period-doubling or quasi-periodic scenarios. In the chaotic regime oscillatory activity undergoes fast temporal decorrelation. The generality of these dynamical properties is assessed in firing-rate models as well as in large networks of conductance-based neurons.



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