Prehyperpolarization caused different phenomena in some subsets of retinal ganglion cells. (A) Rebound excitation. Left upper trace shows the voltage response to the simple reducing of hyperpolarization. Left lower trace shows the voltage response to the strongest stimulating current in tonic range. The current steps were applied from holding current of 320 pA. Right trace also shows the voltage response to the strongest stimulating current in tonic range of this cell, however, the holding current was zero in this recording. The respective maximal steady-state firing frequency did not change profoundly by prehyperpolarization. (B) Ramping. Left upper trace shows the voltage response to the moderate stimulation of prehyperpolarized cell. Left lower trace shows the voltage response to the strongest stimulating current in tonic range. The current steps were applied from holding current of 15 pA. Right trace also shows the voltage response to the strongest stimulating current in tonic range, however, the holding current was zero in this recording. The respective maximal steady-state firing frequency did not change profoundly by prehyperpolarization.

The holding current (HC) and amplitude of depolarizing current step (ADCS) are indicated above each trace. The approximated value of the potential before the stimulus is indicated near each trace by arrow.