Table 2:

IS3 cell signature features, CIPs, measurements, and model elimination criteria

CIP step	Signature feature	Characteristic measurements of feature	Selected IS3 cell measurement values	Elimination criteria (step 2)
−100 pA	Lack of “sag”	(1) Hyperpolarization V_m Difference (mean pulse value − mean initial value)	−34.2649 mV	None
		(2) Minimum potential time	58.9000 ms
		(3) Minimum potential	−112.6709 mV
		(4) Potential sag	6.7865 mV
		5) Sag time constant	14.3000 ms
20 pA	No spiking	(1) Passive depolarization V_m difference (mean pulse value − mean initial value)	12.4910 mV	If spikes are observed
50 pA	Normal spiking	(1) Active depolarization V_m difference (mean pulse value − mean initial value)	29.4174 mV	If fewer than three spikes are observed If membrane potential fails to repolarize
		(2) Interspike interval	36.6898 ms
		(3) First spike time	33.1000 ms
		(4) Spike voltage threshold mean	−44.3428 mV
		(5) Spike half-width mean	1.0301 ms
		(6) Spike amplitude mean	61.7296 mV
		(7) Spike rate	35.0044 Hz
		8) Spike maximum afterhyperpolarization mean	6.8820 mV
		(9) Number of spikes	28.0000
		(10) Spike frequency adaptation	1.3305
500 pA	Depolarization block	(1) Depolarization block V_m difference (final 700 ms mean pulse value − mean initial value)	62.6461 mV	If spikes in the last 700 ms of the CIP are observed If membrane potential fails to repolarize If spikes in the recovery period are observed
500 pA	Depolarization block	(2) Initial 100 ms spike rate	60.0000 Hz

For each CIP step (1st column) we note a signature feature that is observed experimentally (2nd column), characteristic measurements that are used to quantify the signature feature (3rd column), characteristic measurement values from the selected IS3 traces (4th column), as well as conditions where models would be rejected for clearly not capturing the experimental feature (5th column). CIP, Current Injection Protocol; V_m, membrane potential.