Kinetic parameters averaged across a group of neurons with similar shape and orientation to the electric field, separately at the cathode-facing cell poles. The parameters presented are the mean values ± SEM of the maximum optical TMP (the asymptotic ΔFmax, %, determined from the fit equations; note the inverted axis for the anodic pole) and of the charging and discharging time constants (τ, μs). For elongated neurons, the parameters were averaged separately for cells oriented parallel (II,n= 3) and perpendicular (⊥,n= 6) to the electric field. All other cell shapes were designated as “random” (R,n= 10), and the data for the orthogonal field orientations were pooled together. The kinetic parameters were also averaged for all cells and all orientations (ALL,n= 19). #p< 0.01 between charging and discharging time constants (paired two-tailed t test). $p< 0.01 between the orthogonal cell orientations (unpaired two-tailed t test).
