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Inhibitory postsynaptic potentials carry synchronized frequency information in active cortical networks.

Andrea Hasenstaub·Yousheng Shu·Bilal Haider·Udo Kraushaar·Alvaro Duque·David A McCormick
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Abstract

Temporal precision in spike timing is important in cortical function, interactions, and plasticity. We found that, during periods of recurrent network activity (UP states), cortical pyramidal cells in vivo and in vitro receive strong barrages of both excitatory and inhibitory postsynaptic potentials, with the inhibitory potentials showing much higher power at all frequencies above approximately 10 Hz and more synchrony between nearby neurons. Fast-spiking inhibitory interneurons discharged strongly in relation to higher-frequency oscillations in the field potential in vivo and possess membrane, synaptic, and action potential properties that are advantageous for transmission of higher-frequency activity. Intracellular injection of synaptic conductances having the characteristics of the recorded EPSPs and IPSPs reveal that IPSPs are important in controlling the timing and probability of action potential generation in pyramidal cells. Our results support the hypothesis that inhibitory networks are largely responsible for the dissemination of higher-frequency activity in cortex.

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Action PotentialsAnimalsCerebral CortexCortical SynchronizationExcitatory Postsynaptic PotentialsFerretsIn Vitro TechniquesInterneuronsMaleMembrane PotentialsNerve NetNeural InhibitionNeuronsOscillometryPyramidal CellsReaction TimeRefractory Period, ElectrophysiologicalSynapsesSynaptic TransmissionJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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BibTeXRIS

Andrea Hasenstaub, Yousheng Shu, Bilal Haider, Udo Kraushaar, Alvaro Duque, David A McCormick. 2005-08-04. Inhibitory postsynaptic potentials carry synchronized frequency information in active cortical networks.. https://doi.org/10.1016/j.neuron.2005.06.016

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