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Electrical Interactions via the Extracellular Potential Near Cell Bodies

Holt, Gary R. and Koch, Christof (1999) Electrical Interactions via the Extracellular Potential Near Cell Bodies. Journal of Computational Neuroscience, 6 (2). pp. 169-184. ISSN 0929-5313. doi:10.1023/A:1008832702585.

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Ephaptic interactions between a neuron and axons or dendrites passing by its cell body can be, in principle, more significant than ephaptic interactions among axons in a fiber tract. Extracellular action potentials outside axons are small in amplitude and spatially spread out, while they are larger in amplitude and much more spatially confined near cell bodies. We estimated the extracellular potentials associated with an action potential in a cortical pyramidal cell using standard one-dimensional cable theory and volume conductor theory. Their spatial and temporal pattern reveal much about the location and timing of currents in the cell, especially in combination with a known morphology, and simple experiments could resolve questions about spike initiation. From the extracellular potential we compute the ephaptically induced polarization in a nearby passive cable. The magnitude of this induced voltage can be several mV, does not spread electrotonically, and depends only weakly on the passive properties of the cable. We discuss their possible functional relevance.

Item Type:Article
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URLURL TypeDescription
Koch, Christof0000-0001-6482-8067
Additional Information:Received March 16, 1998; Revised August 31, 1998; Accepted September 2, 1998. c1999 Kluwer Academic Publishers. We thank David Kewley and James Bower for helpful discussions about electrical potentials and ephaptic interactions and Zachary Mainen and Terrence Sejnowski for making their model of a cortical pyramidal cell available on the web. The research reported here was supported by the Sloan Center for Theoretical Neuroscience at Caltech as well as by the NIMH and NSF.
Group:Koch Laboratory (KLAB)
Funding AgencyGrant Number
Sloan Center for Theoretical NeuroscienceUNSPECIFIED
Subject Keywords:extracellular field potential ; volume conduction ; branch point failure ; axon hillock/initial segment
Issue or Number:2
Record Number:CaltechAUTHORS:20130816-103241377
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:40557
Deposited By: KLAB Import
Deposited On:15 Jan 2008 22:13
Last Modified:09 Nov 2021 23:49

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