Biophysical characterization of INC mutations. (A) Sodium currents in response to command depolarization to voltages from −90 mV to +60 mV. Effects of INC mutations are shown for activation (B), steady-state fast inactivation (C), entry into fast inactivation (D and E), and recovery (F and G). Legends identify residues and locus by domain and segment. Values represent mean ± SEM (error bars) from 10–23 experiments.