<p>A. The maximum of Na<sup>+</sup> inactivation time constant τ<sub>h</sub> decreases as temperature increases for the normal model (control; black). For the test group, the maximum of Na<sup>+</sup> inactivation time constant τ<sub>h</sub> is invariant with temperature change (red). B. The Na<sup>+</sup> entry ratio decreases as a function of temperature for control (black), while the Na<sup>+</sup> entry ratio increases as a function of temperature when the inactivation time constant of I<sub>Na</sub> (τ<sub>h</sub>) is fixed. Keeping I<sub>Na</sub> activation time constant (τ<sub>m</sub>) invariant or I<sub>K</sub> activation time constant (τ<sub>n</sub>) invariant with temperature reveals effects of temperature on Na<sup>+</sup> excess entry similar to that in control. C. The half-height spike duration decreases as a function of temperature for the control group (black), while it becomes relatively independent to temperature change when I<sub>Na</sub> inactivation time constant, τ<sub>h</sub>, is invariant. The test group with invariant τ<sub>m</sub>, or τ<sub>n</sub>, has similar behavior as that in control group. D. Example membrane potential and I<sub>Na</sub>, I<sub>K</sub> for 11, 23, and 37°C when the time constant of I<sub>Na</sub> inactivation (τ<sub>h</sub>) is kept constant. Note that the overlap of Na<sup>+</sup> and K<sup>+</sup> currents becomes larger with temperature, which is opposite to the normal situation (see <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002456#pcbi-1002456-g001" target="_blank">Figure 1B</a>).</p
