Enhanced neuronal response induced by fast inhibition.
We report a facilitatory role of inhibitory synaptic input that can enhance a neuron's firing rate, in contrast to the conventional belief that inhibition suppresses firing. We study this phenomenon using the Hodgkin-Huxley model of spike generation with random Poisson trains of subthreshold excitatory and inhibitory inputs. Enhancement occurs when, by chance, brief inhibition leads excitation with a favorable timing and counterintuitively induces a reduction of the spike threshold. The basic mechanism is also illustrated with the phase-plane analysis of a two variable model.
Center for Neural Science, New York University, New York, NY 10003, USA.
Ramana
R
Dodla
John
J
Rinzel
D000818:Animals; D001703:Biophysics / Q000379:methods; D001921:Brain / Q000378:metabolism; D006801:Humans; D008564:Membrane Potentials; D008962:Models, Theoretical; D009474:Neurons / Q000378:metabolism*; D016012:Poisson Distribution; D013997:Time Factors