Fig. 10.

Light-evoked input currents to a ganglion cell were similar under current and voltage clamp. A, Average of 18 responses to a 10 msec light flash measured under voltage clamp. Holding potential: −60 mV. B, Post-stimulus time histograms of spike responses measured under current clamp. The thick trace plots the average firing rate to 28 light flashes identical to those used in A. The thin trace plots the average firing rate to 26 trials in which the current–response from A was used as a current-clamp command signal. The similarity of the light-evoked and current-evoked changes in firing rate indicate that the light-evoked currents reaching the ganglion cell soma are similar under current and voltage clamp. Holding current: −5 pA. Flash strength: 1000 photons μm⁻² sec.