title: Estimating the biophysical properties of neurons with intracellular calcium dynamics.
abstract: We investigate the dynamics of a conductance-based neuron model coupled to a model of intracellular calcium uptake and release by the endoplasmic reticulum. The intracellular calcium dynamics occur on a time scale that is orders of magnitude slower than voltage spiking behavior. Coupling these mechanisms sets the stage for the appearance of chaotic dynamics, which we observe within certain ranges of model parameter values. We then explore the question of whether one can, using observed voltage data alone, estimate the states and parameters of the voltage plus calcium (V+Ca) dynamics model. We find the answer is negative. Indeed, we show that voltage plus another observed quantity must be known to allow the estimation to be accurate. We show that observing both the voltage time course V(t) and the intracellular Ca time course will permit accurate estimation, and from the estimated model state, accurate prediction after observations are completed. This sets the stage for how one will be able to use a more detailed model of V+Ca dynamics in neuron activity in the analysis of experimental data on individual neurons as well as functional networks in which the nodes (neurons) have these biophysical properties.
authors.affiliation: Department of Physics, University of California, San Diego, La Jolla, California 92093-0374, USA.
authors.forename: Jingxin
authors.initials: J
authors.lastname: Ye
authors.affiliation: Department of Physics, University of California, San Diego, La Jolla, California 92093-0374, USA.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Rozdeba
authors.affiliation: Department of Physics, University of California, San Diego, La Jolla, California 92093-0374, USA.
authors.forename: Uriel I
authors.initials: UI
authors.lastname: Morone
authors.affiliation: Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60647, USA.
authors.forename: Arij
authors.initials: A
authors.lastname: Daou
authors.affiliation: Department of Physics and Marine Physical Laboratory (Scripps Institution of Oceanography) University of California, San Diego La Jolla, California 92093-0374, USA.
authors.forename: Henry D I
authors.initials: HD
authors.lastname: Abarbanel
mesh_terms: D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000378:metabolism; D042541:Intracellular Space / Q000378:metabolism; D008564:Membrane Potentials / Q000502:physiology; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D013997:Time Factors
chemical_list: D015220:Calcium Channels; D002118:Calcium