Selectivity of microelectrodes in recordings from cat retinal ganglion cells

Abstract

A comparison was made between the proportions of presumptive Y cells, presumptive X cells, and presumptive W cells recorded extracellularly with two different types of electrode: 3.5 M NaCl filled micropipettes with impedances at 50 Hz greater than 7 MΩ and tungsten in glass eectrodes of microscopically specified size and shape. In order to exclude the effect of a varying proportion of different classes of cells at different eccentricities from the area centralis, a series of comparisons was made over limited ranges of eccentricity. Both kinds of electrodes successfully isolated the various types of ganglion cells in about the same relative proportions. There was no systematic differential selectivity either between the two classes of electrodes or as a function of impedance within each class. (18 references.) Show more