Fig. 11.

Firing properties of the FS cell type. The cell depicted here is the same as that in Figure10A–C. A, Sample traces of this cell firing in response to three successively larger 500 msec current pulses. The amplitudes of the current pulses are indicated to theright of each trace. For moderate current amplitudes, the cell fired intermittently. The baseline potential was −55 mV.B, Histogram of interspike intervals for this cell during +0.35 nA current pulses (three repetitions). This shows two populations of interspike intervals: short (<30 msec) intraburst intervals and longer (>40 msec) interburst intervals (“pauses”).C, Firing rate of this cell as a function of injected current. Filled circles show the firing rate averaged over the entire current pulse; open circlesshow the firing rate during current levels that evoked intermittent firing, excluding the pauses. This rate was defined as the inverse of the intraburst interspike interval (i.e., excluding intervals that were >40 msec). These points were an average of one to three repetitions of each current pulse.