The relationship between cross-correlation measures and underlying synaptic events.

D J Surmeier; R J Weinberg

doi:10.1016/0006-8993(85)90732-2

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The relationship between cross-correlation measures and underlying synaptic events.

D J Surmeier·R J Weinberg

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Abstract

The relationship between an excitatory postsynaptic potential (EPSP) and the cross-correlation derived from the spike train evoked by a Poisson stimulus train was studied by computer stimulation. The neuron model had a constant threshold and an absolute refractory period. Following a spike, the membrane potential was determined by ongoing activity, i.e., it was not 'reset'. Under all conditions studied, the rise time of the cross-correlation peak accurately reflected EPSP rise time. The agreement between the half-width of the cross-correlation peak and that of the underlying EPSP depended upon the EPSP amplitude, the rate of the driving Poisson input, and the time course of the EPSP. Over a broad range of experimentally relevant conditions, the half-width of the cross-correlation peak deviated from that of the underlying EPSP by less than 30% and bore little resemblance to that of the EPSP's time derivative.

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Evoked Potentials Medulla Oblongata Models, Neurological Synapses Synaptic Transmission Journal Article Research Support, U.S. Gov't, P.H.S.

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D J Surmeier, R J Weinberg. 1985-04-01. The relationship between cross-correlation measures and underlying synaptic events.. https://doi.org/10.1016/0006-8993(85)90732-2

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