Gating information by two-state membrane potential fluctuations

Kepecs, A., Raghavachari, S. (April 2007) Gating information by two-state membrane potential fluctuations. J Neurophysiol, 97 (4). pp. 3015-23. ISSN 0022-3077 (Print)

Abstract

Two-state voltage fluctuations between a hyperpolarized down-state and a depolarized up-state have been observed experimentally in a wide variety of neurons across brain regions. Using a biophysical model, we show that synaptic input by NMDA receptors can cause such membrane potential fluctuations. In this model, when a neuron is driven by two input pathways with different AMPA/NMDA receptor content, the NMDA-rich input causes up-state transitions, whereas the AMPA-rich input generates spikes only in the up-state. Therefore the NMDA-rich pathway can gate input from an AMPA pathway in an all-or-none fashion by switching between different membrane potential states. Furthermore, once in the up-state, the NMDA-rich pathway multiplicatively increases the gain of a neuron responding to AMPA-rich input. This proposed mechanism for two-state fluctuations directly suggests specific computations, such as gating and gain modulation based on the distinct receptor composition of different neuronal pathways. The dynamic gating of input by up- and down-states may be an elementary operation for the selective routing of signals in neural circuits, which may explain the ubiquity of two-state fluctuations across brain regions.

Item Type: Paper
Uncontrolled Keywords: Algorithms Brain/cytology/ physiology Dendrites/physiology Electrophysiology Excitatory Postsynaptic Potentials/physiology Ion Channel Gating/physiology Membrane Potentials/ physiology Models, Neurological Nerve Net/cytology/physiology Neurons/ physiology Poisson Distribution Receptors, AMPA/physiology Receptors, N-Methyl-D-Aspartate/ physiology
Subjects: bioinformatics > genomics and proteomics > annotation > map annotation
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > NMDA receptor
Investigative techniques and equipment > electrophysiology
CSHL Authors:
Communities: CSHL labs > Kepecs lab
Depositing User: CSHL Librarian
Date: April 2007
Date Deposited: 11 Nov 2011 17:04
Last Modified: 03 Dec 2014 17:58
Related URLs:
URI: https://repository.cshl.edu/id/eprint/23061

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