Figure 7.

Extracellular-to-ground impedance for a nonarborized neuron in culture. (A) Modulus of the impedance as a function of frequency. (B) Phase of the impedance as a function of frequency. Dotted lines correspond to the mathematical model given by Eq. 3b (Fig. 5 and Online Appendix A). The different fits shown are: Blue: NMD - Membrane + diffusive intracellular and extracellular media; Red: NMR - Neuron in a non-negligible resistive medium $z_e^{\left(m\right)}\ne 0$; Gray: experimental measurement; Black: For (A), cubic spline of the logarithm of the modulus and frequency of experimental data; for (B): cubic spline of the phase and logarithm of frequency. Parameters: in all models, R_m = 10 MΩτ_m = 25 ms, r_d = 2 μm, l_d = 100 μm and Z_g = 0.1 MΩ; NMR: ${\sigma }_e^i=5S/m$, $\frac{z_m^{\left(e\right)}}{r_m}=0.5$, NMD: ν_wT = 0.01 Hz, $\frac{z_e^{\left(m\right)}}{r_m}=0.5+\frac{0.5}{1+\sqrt{i\frac{\omega }{{\omega }_{wT}}}}$, $\pi r_d^2\cdot z_i=\frac{1}{{\sigma }_e^i}+\frac{1}{1+\sqrt{i\frac{\omega }{{\omega }_{wT}}}}$. To see this figure in color, go online.