Figure 7.

The sub-critical state of the fractional Hodgkin–Huxley (fHH) circuit. (A) Relative firing rate (solid) in response to $1Hz$ frequency and $0.01mA$ amplitude input signal with varying DC values ($0.10,\text{black}-0.25\text{mA},\text{red}$). Dashed lines are fits. (B) The amplitude (gain) and phase shift with respect to input signal from (A). (C) Phase advance in the sub-critical regime $(DC=0.26mA$ and $0.05mA$ amplitude at $1Hz$). The phase advance results in a fractional order derivative of $\eta =0.23\pm 0.0195\%\text{CI}$. Firing rate, solid red; fit, dashed red; input, solid black.