Figure 7.

The firing of DCN neurons evoked by a series of current steps. A series of current steps of increasing and then decreasing amplitude were used to stimulate DCN neurons (C, top). For different trials, the durations of the current steps were 0.3, 1, 3, 10, and 30 s. These steps are delivered in addition to a 100 pA current used to maintain baseline firing at rates similar to those observed in vivo. A, Instantaneous firing frequencies evoked by 1 s (left) and 30 s (right) current steps are shown for a DCN neuron. B, Responses of the DCN cell in A are shown to illustrate the differences between 1 s steps and 30 s steps. The initial 100 ms (black) and the final 100 ms (blue) are shown for each current step. For 1 s steps, the firing frequencies at the start of current steps are proportional to the magnitude of the current step, and firing frequencies remained similar during current steps. For 30 s steps, firing frequencies slowly adapt, resulting in very different firing frequencies at the start and the end of each step. C, Summary of the firing responses to current steps of varying duration. Plots on the left show the average instantaneous firing frequency of DCN cells in response to the depolarizing current ramp where each step is of the indicated duration. The SE is shaded in gray. Plots on the right show the average firing rates for the initial (black) and final (blue) 100 ms (n = 7 cells, n = 6 animals).