Signal to noise ratio in PRC estimates.

PRCs were smoothed and normalized by the total charge of the injected pulse Q = I_pulse ⋅ T_pulse. Increasing the amplitude I_pulse increased the estimates confidence (A-B), reducing the standard deviation of the PRC raw data points, especially as PCs fire at low firing rates. The plots display the PRC estimates obtained without the PID controller for I_pulse = 50 and 100 pA, in the same PC over a comparable number of stimulation trials (i.e., 1911 and 1338 at high firing rates, and 3361 and 3350 at low firing rates, respectively). The smoothed PRCs and their 68% confidence intervals (C-D) are plotted, as a function of time (i.e., τ = (φ − 1) ⋅ ⟨ISI⟩) by the lines and shaded areas (i.e., dashed/gray for 50 pA and continuous/white for 100 pA).