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Action Potential Initiation

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Encyclopedia of Computational Neuroscience
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Synonyms

Spike initiation

Definition

Electrical impulses (action potentials (APs) or spikes) which encode and transmit information in the nervous system are initiated in the proximal anatomical region of the axon termed axon initial segment (AIS). The voltage threshold for spike initiation and the exact location and length of the spike trigger zone (TZ) within AIS, as well as the amplitude and waveform of the action potential in different neuronal classes, depend on the geometry and passive electrical properties of a neuron as well as on the type, spatial distribution, and density of a variety of voltage-sensitive ionic channels.

Detailed Description

There is little disagreement over attributing action potential initiation to a site in the axon initial segment (AIS) under most circumstances. The question of the exact location and length, however, of the spike trigger zone (TZ) in the axon, as defined in functional terms, is less clear. In most studies, the spike TZ was characterized by...

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Correspondence to Dejan Zecevic .

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Zecevic, D., Popovic, M. (2014). Action Potential Initiation. In: Jaeger, D., Jung, R. (eds) Encyclopedia of Computational Neuroscience. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-7320-6_237-1

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  • DOI: https://doi.org/10.1007/978-1-4614-7320-6_237-1

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  • Online ISBN: 978-1-4614-7320-6

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