Estimated statistical and systematic errors in the six human L2/3 PCs models shown in Figure 1 as in (Roth and Häusser, 2001). The mean relative statistical error was 6.5% in Cm (range, 4.2-9.2%, n = 5), 8.6% in Rm (range, 4.2-18.8%, n = 5), and 12.8% in Ra (range, 5.3-20.2%, n = 5). In cell #060311, larger errors were found due to several noisy traces. These range of errors in the estimated values of Cm, Rm and Ra, are within the range of values found for the six modeled cells in Figure 1. We also analyzed the case of systematic errors; the errors introduced are shown in Table 3. This leads to, 40% mean relative error in Cm (range, 36.7–58.2%, n = 6), 30.1% in Rm (range, 28.6–34.1%, n = 6), and 53.0% in Ra (range, 47.3–65.4%, n = 6). Thus, even large systematic errors in morphological parameters cannot explain the low Cm (~0.5 µF/cm2) in human L2/3 pyramidal neurons as compared to the typical value ~1 µF/cm2 found in other neurons.