Daniel Wojcik
(http://www.neuroinf.pl/Members/danek/)
Nencki Institute for Experimental Biology, Polish Academy of Sciences
Wednesday 24th October 2012
Time: 4pm
B10 Seminar Room, Basement,
Alexandra House, 17 Queen Square, London, WC1N 3AR
Kernel methods for current source density reconstruction
Local field potentials (LFP), the low-frequency part of extracellular electrical recordings, are a measure of the neural activity reflecting dendritic processing of synaptic inputs to neuronal populations. To localize synaptic dynamics it is convenient, whenever possible, to estimate the density of trans-membrane current sources (CSD) generating the LFP.
I will present a new framework, kernel Current Source Density method (kCSD), which allows for non-parametric estimation of CSD from LFP recorded from arbitrarily distributed electrodes, using kernel methods. I will show specific implementations of this framework on model data measured with one-, two-, and three-dimensional multielectrode setups. These methods will be compared with the traditional approach through numerical approximation of the Laplacian and with the recently developed inverse Current Source Density methods (iCSD). The proposed method opens up new experimental possibilities of CSD analysis from already taken or new recordings on arbitrarily distributed electrodes (not necessarily on a grid), which can be obtained in extracellular recordings of single unit activity with multiple electrodes.
If time allows, II will also show that independent components of reconstructed CSD reflect activity of individual cell populations.