title: Impact of slow K(+) currents on spike generation can be described by an adaptive threshold model.
abstract: A neuron that is stimulated by rectangular current injections initially responds with a high firing rate, followed by a decrease in the firing rate. This phenomenon is called spike-frequency adaptation and is usually mediated by slow K(+) currents, such as the M-type K(+) current (I M ) or the Ca(2+)-activated K(+) current (I AHP ). It is not clear how the detailed biophysical mechanisms regulate spike generation in a cortical neuron. In this study, we investigated the impact of slow K(+) currents on spike generation mechanism by reducing a detailed conductance-based neuron model. We showed that the detailed model can be reduced to a multi-timescale adaptive threshold model, and derived the formulae that describe the relationship between slow K(+) current parameters and reduced model parameters. Our analysis of the reduced model suggests that slow K(+) currents have a differential effect on the noise tolerance in neural coding.
authors.affiliation: Principles of Informatics Research Division, National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo, Japan. r-koba@nii.ac.jp.|Department of Informatics, SOKENDAI (The Graduate University for Advanced Studies), 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo, Japan. r-koba@nii.ac.jp.
authors.forename: Ryota
authors.initials: R
authors.lastname: Kobayashi
authors.affiliation: Department of Human and Computer Intelligence, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Kitano
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000222:Adaptation, Physiological; D000818:Animals; D004553:Electric Conductivity; D006801:Humans; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D011189:Potassium Chloride / Q000378:metabolism*
chemical_list: D011189:Potassium Chloride
keywords: Conductance-based models; Integrate-and-fire models; Model reduction; Slow K+ currents; Spike generation mechanism