Figure 4.

The rising slopes and threshold potentials in two AISS phases are different, in which phase two is dependent upon phase one. A) shows an expanded waveform of AISS that has a step-like upstroke with Vts one and two. B) shows a phase-plot for this expanded AISS waveform that is divided into two phases with slope one and two. C) illustrates a plot of slope two versus slope one from twenty-nine GABAergic neurons. The slope for phase one is larger than that for phase two, and CV of slope two is larger than CV of slope one (inset). There is a linear correlation between slope two and slope one (r² = 0.58). D) illustrates phase-plot for the expanded waveforms of AISS that is divided into two phases from a neuron. E) shows a plot of slope two versus slope one from this neuron. F) illustrates a linear correlation between slope two versus inter-phase intervals (IPI) this neurons, i.e., the onset of phase two is influenced by the refractory period of phase one.