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PubMed · 8672560

Neuron as time coherence discriminator.

A K Vidybida
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Abstract

Neuronal excitability under stimuli with a complex time course is investigated on the basis of the numerical solution of the Hodgkin-Huxley equations. Each stimulus is composed of 100-1000 unitary excitatory postsynaptic potentials (uEPSP) that start randomly within a definite time window. Probability of initiating a spike [firing probability, FP(W)] as a function of the window width W is calculated by the Monte Carlo method. FP(W) has a step-like shape: it becomes equal to 1 for small W and almost vanishes as W exceeds some value Ws. The role of long-lasting somatic inhibition is analysed. Ws depends on the inhibition potential, but the step-like shape of FP is preserved. It is concluded that the capability of multisynaptic stimulation to cause a spike can be expressed in terms of temporal coherence between the synaptic inputs. Namely, the spike is initiated if the temporal coherence between active inputs is above a definite threshold. The threshold value can be effectively regulated by varying the inhibition potential.

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Action PotentialsAnimalsComputer SimulationModels, NeurologicalMonte Carlo MethodNeuronsSynaptic TransmissionTimeJournal Article

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BibTeXRIS

A K Vidybida. 1996. Neuron as time coherence discriminator.. https://doi.org/10.1007/bf00209424

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