Journal of Neurophysiology, Vol 38, Issue 2 369-382, Copyright © 1975 by APS
Experimental optimization of current source-density technique for anuran cerebellum
J. A. Freeman and C. Nicholson
This paper represents a systematic, semirigorous attempt to optimize the
technique of current source-density (CSD) analysis experimentally. We
compared different spatial differentiation formulas in terms of accuracy,
aliasing, and smoothing, and provide experimental and theoretical rationale
for their use. Sources of error have also been investigated. Expressions
were derived to enable one to estimate the relative magnitude of errors due
to electrical noise, uncertainty in tip position of recording electrodes,
and error in the conductivity tensor. Corresponding experiments
illlustrating the validity of such estimates are also presented. Methods to
determine the optimum interelectrode spacing are given, based on
computations of spatial energy-density spectra in the anuran cerebellum.
The application of the technique of CSD analysis developed in this, and the
accompanying paper, to the vestibulocerebellar input in the toad cerebellum
provided significantly better temporal and spatial resolution of neuronal
events than conventional field-potential analysis. Considerations germane
to the optimum application of this technique to other neural structures are
also discussed.
