Fig. 2.
Spike-timing precision increased with input gain and input synchronization. A, Stimulus-aligned spike rasters, voltage traces, and cross-correlograms of one DCN neuron at a high level of input synchronization. At the input gain of 16, the percentage of all spikes that were precisely aligned within a window of ±5 msec in the cross-correlogram of this neuron was 67% (shuffle corrected). B, Spike rasters, voltage traces, and cross-correlograms of the same neuron when an intermediate input synchronization was used. The proportion of precisely timed spikes (±5 msec) was reduced to 35% at a gain of 16. C, Average spike-timing precision of recorded DCN neurons (mean ± SE) as a function of the input gain and synchronization. Numbers of cells averaged were 19 for high, 12 for intermediate, and 12 without input synchronization. The precision criterion is the shuffle-corrected percentage of spikes that fell into a time window of ±5 msec in the cross-correlogram (see Materials and Methods). D, Same data as in C for a different precision criterion (±1 msec). E, Spike-timing precision (criterion, ±5 msec) as a function of the number of synchronized input elements at an input gain of 2 and 8 (n = 6). Note that inE input elements were synchronized only within one group in contrast to the synchronization inA–D.