**(A)** shows the effect of increasing *I*_{ratio} to 0.5 from 0 on the ISI distributions generated by the HH model at 2.3 and 9 spikes/s (*R*_{epsc} was adjusted to 694 and 1304 Hz to achieve firing rates of 2.3 and 9 spikes). Model distributions (pink; *I*_{ratio} = 0.5, *g*_{BK} = 1) are superimposed on ISI distributions from the reference data in Fig 1 (blue). Increasing *I*_{ratio} increases the number of short ISIs, and the model ISI distribution no longer matches the reference data. **(B)** shows the effect of increasing *g*_{BK} to 3.2 mS/cm^{2}, with *R*_{epsc} adjusted to 694 and 1290 Hz to achieve firing rates of 2.3 and 9 spikes/s. ISI distributions from the adjusted model (purple; *I*_{ratio} = 0.5, *g*_{BK} = 3.2) are superimposed on ISI distributions from the reference data in Fig 1 (blue). By increasing *g*_{BK}, a good fit can again be obtained. **(C)** shows the ‘average spike waveform’ for three different runs of the model–*I*_{ratio} = 0 in green (from Fig 6B), *I*_{ratio} = 0.5, *g*_{BK} = 1 in pink, and *I*_{ratio} = 0.5, *g*_{BK} = 3.2 in purple. Increasing *I*_{ratio} results in an attenuation of the observed HAP, which can be reversed by increasing *g*_{BK}, restoring a good fit to the *in vivo* reference data.