Fig. 1.

Voltage inside CA1 layer nearly linearly depends on direct current (DC) amplitude. A and C: position of the recording electrode in CA1 region and positions of two DC silver-chloride (AgCl) electrodes in “horizontal” and “vertical” configurations, respectively. B and D: dependence of the voltage in CA1 region measured relative to the “gray” AgCl electrode as a function of the DC amplitude. Positive DC values correspond to positive potential of “white” DC electrode relative to gray DC electrode. Number of slices per condition is 6 or 7. Error bars correspond to SE.