Figure 1.

Theoretical prediction of increased efficiency of optocapacitance as photostimulating pulse duration is decreased. (A) Equivalent circuit of the membrane shows V as the transmembrane voltage, C_m as the membrane capacitance, V_S as the net surface potential of the membrane, I_C as the capacitive current, R_m as the membrane resistance, V_r as the reversal potential of the ionic current, and I_i as the ionic current. Arrows indicate the outward current direction. (B) Plots of Eq. 7 predict the fractional increase in C_m during laser pulses of different powers with the highest as the top trace and the lowest as the bottom trace. (C) Time derivative of C_m that was plotted in (B), predicting that I_C is highest at the time of pulse initiation and then decays with time. To see this figure in color, go online.