21 February 2023
09:30 - 11:00 AM
4KD503 (in person) and available via zoom
Claude Bedard (CNRS)

Generalized Cable Theory and Impedance of the Neural Tissue

This is a joint Krembil Computational Neuroscience (KCN)/Center for Mathematical Medicine (CMM) seminar.


Hybrid presentation: In person at KDT (4KD503) and via zoom link below

Abstract: Cable theory is fundamental to understanding neurons' electric behavior and their extended dendritic structure. This theory was introduced by Wilfrid Rall more than half a century ago and is widely used today for modeling the voltage and current flow in neuronal and dendritic structures. The classic cable theory was derived assuming that the extracellular medium is either inexistent or modeled as a resistor. For modeling neurons in more realistic situations, where the extracellular medium has more complex electric properties, it is necessary to generalize Rall's cable equations. We present such generalized cable equations and show that the nature of the surrounding extracellular medium can exert non-negligible influences on the cable properties of neurons.

Brief Bio: Claude Bedard is a physicist affiliated with the CNRS and the College de France. He holds a Ph.D. in Theoretical Physics from the Université Laval (Québec, PQ, Canada) and pursued his postdoctoral training at the group of computational and experimental neuroscience of renowned neuroscientist Alain Destexhe, at CNRS, Gif-sur-Yvette, in France. Claude is an expert in classical electrodynamics and has made pioneering contributions in extending Maxwell's equations and cable theory to studying electromagnetic phenomena in brain tissue.       

Short reference list:
  1. Claude Bedard, Charlotte Piette, Laurent Venance, Alain Destexhe: (2022) Extracellular and intracellular components of the impedance of neural tissue Biophysical Journal,121, 869-885, 2022.
  2. Bédard, C. and Destexhe, A.: Generalized Cable Models of Neuron and Dendrites. Neuroscience in the 21 st Century, Springer New York, NY, 2021.
  3. Claude Bedard, Jean-Marie Gomes, Thierry Bal, Alain Destexhe: A framework to reconcile frequency scaling measurements, from intracellular recordings, local-field potentials, up to EEG and MEG signals. Journal of integrative neuroscience 2017; 16 (1) .
  4. Jean-Marie Gomes, Claude Bédard, Silvana Valtcheva, Matthew Nelson, Vitalia Khokhlova, Pierre Pouget, Laurent Venance, Thierry Bal, Alain Destexhe: Intracellular Impedance Measurements Reveal Non-ohmic Properties of the Extracellular Medium around Neurons. Biophysical Journal 2016; 110(1).
  5. Claude Bédard, Alain Destexhe: Mean-Field Formulation of Maxwell Equations to Model Electrically Inhomogeneous and Isotropic Media. Journal of Electromagnetic Analysis and Applications 2014; 6(10).
  6. Claude Bédard, Alain Destexhe: Generalized cable formalism to calculate the magnetic field of single neurons and neuronal populations. Physical Review E 2014; 90(4).
  7. Claude Bédard, Alain Destexhe: Generalized cable theory for neurons in complex and heterogeneous media. Physical Review E 2013; 88(2).
  8. Bédard, C. and Destexhe, A.,: Modeling local field potentials and their interaction with the extracellular medium. Chapter 4, Handbook of Neural Activity Measurement, Cambridge University Press, 2012.
  9. Claude Bédard, Alain Destexhe: Generalized theory for current-source-density analysis in brain tissue. Physical Review E 2011; 84(4 Pt 1).
  10. Bédard, C., Kröger, H. and Destexhe, A., Does 1/f frequency scaling of brain signals reflect self-organized critical states? Physics Review Letters 97, 118102, 2006.
  11. Bédard, C., Kröger, H. and Destexhe, A., Modeling extracellular field potentials and the frequency filtering properties of extracellular space.. Biophysical Journal 86, 1829-42, 2004.

Recording available on kcnhub youtube channel