Dynamic I-V curves are reliable predictors of naturalistic pyramidal-neuron voltage traces.
Neuronal response properties are typically probed by intracellular measurements of current-voltage (I-V) relationships during application of current or voltage steps. Here we demonstrate the measurement of a novel I-V curve measured while the neuron exhibits a fluctuating voltage and emits spikes. This dynamic I-V curve requires only a few tens of seconds of experimental time and so lends itself readily to the rapid classification of cell type, quantification of heterogeneities in cell populations, and generation of reduced analytical models. We apply this technique to layer-5 pyramidal cells and show that their dynamic I-V curve comprises linear and exponential components, providing experimental evidence for a recently proposed theoretical model. The approach also allows us to determine the change of neuronal response properties after a spike, millisecond by millisecond, so that postspike refractoriness of pyramidal cells can be quantified. Observations of I-V curves during and in absence of refractoriness are cast into a model that is used to predict both the subthreshold response and spiking activity of the neuron to novel stimuli. The predictions of the resulting model are in excellent agreement with experimental data and close to the intrinsic neuronal reproducibility to repeated stimuli.
Laboratory of Computational Neuroscience, School of Computer and Communication Sciences and Brain Institute, Lausanne, Switzerland.
Laurent
L
Badel
Sandrine
S
Lefort
Romain
R
Brette
Carl C H
CC
Petersen
Wulfram
W
Gerstner
Magnus J E
MJ
Richardson
D000818:Animals; D000831:Animals, Newborn; D002540:Cerebral Cortex / Q000166:cytology; D004056:Differential Threshold; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation; D004560:Electricity; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000502:physiology / Q000528:radiation effects; D051379:Mice; D008810:Mice, Inbred C57BL; D008959:Models, Neurological; D017711:Nonlinear Dynamics; D018408:Patch-Clamp Techniques / Q000379:methods; D017966:Pyramidal Cells / Q000502:physiology* / Q000528:radiation effects*