Example dwell-time histograms of single channel recordings. (A) Dwell-time histogram of the closed states of a single MEC-4d/10d + MEC-2 + MEC-6 channel. (B) Dwell-time histogram of the open states of the same channel as in A. For optimal visual estimation of fit quality (Sigworth and Sine, 1987), dwell times are accumulated into logarithmic bins and displayed with a square-root ordinate. Solid lines are fits to the data with the sum of three exponential functions, dotted lines represent each exponential component.