Figure 8.

Accumulation of depression with multiple preceding impulses does not differ between sustained and transient neurons. A, Diagram of the method of spike selection. Spontaneous activity in sustained and transient neurons was studied. Spikes with short preceding interspike intervals (5–20 ms) were selected for analysis (top, vertical arrows). For each of these spikes, we examined the preceding 200 ms and compared those short-interval spikes that had only a single preceding spike during this period (middle, vertical arrow) with those that had at least five spikes during this period (bottom, vertical arrow). B, For both sustained and transient cells, post-synaptic responses generated by spikes with short preceding intervals were of somewhat lower amplitude if they followed periods of high activity (5 or more spikes) compared with those with only a single spike during this interval. Data points show the mean normalized amplitude (compared with spikes with long preceding intervals of 500–3000 ms) ± SEM.