(A) Schematic of the virtual protocol for somatic (top) and somatodendritic (bottom) synaptic inputs. Representative O-LM model morphology shown with soma and dendrites (black) and truncated axon (green). Excitatory and inhibitory Poisson process synaptic inputs shown in grey box; note that each synaptic input location has an independent excitatory and inhibitory Poisson process. Synaptic inputs are tuned to produce approximately 2.5 Hz output prior to input modulation. Only the inhibitory inputs are modulated (‘~' symbol). See Materials and methods for full details. (B) Locations of synaptic inputs when distributed along soma and dendrites (SD inputs case; see Materials and methods) for both O-LM cell morphologies (cell 1, left; cell 2, right; dendrites in black; soma in blue with surrounding dashed black ellipse; truncated axon in grey; synaptic input locations in orange). The case with somatic inputs contains only one input location at the middle of the soma (not shown). (C) Example somatic voltage traces from a model with somatodendritic H (HSD, rank 109) showing spike trains with 8 Hz modulation for somatic inputs (S-I, top) and somatodendritic inputs (SD-I, bottom). Orange bars at bottom denote peak phase of modulation at 8 Hz (see Materials and methods). (D) Mean subthreshold Vm for models with somatic (HS) vs. somatodendritic (HSD) H distributions and somatic inputs (S-I) vs. somatodendritic (SD-I) inputs, all with no modulation (HS: no significant difference, n = 16; HSD: ***p<0.001, n = 16; Wilcoxon rank sum test performed for both cases). (E) Fluctuations of subthreshold Vm of models with HS vs. HSD and S-I vs. SD-I, all with no modulation, as measured by the standard deviation of subthreshold Vm. (HS: **p<0.01, n = 16, Wilcoxon rank sum test; HSD: ***p<0.001, n = 16, paired t-test). (F) Spike rates of models with HS vs. HSD and S-I vs. SD-I, all with no modulation, with no significant difference for both HS and HSD cases (n.s., n = 16 each; paired t-test performed for both). (G) Power ratio, or ratio of power at modulation frequency to 0 Hz frequency, for models with HS (somatic H, left) and HSD (somatodendritic H, right), with S-I (blue) and SD-I (orange). Power ratios are significantly higher for all modulation frequencies for both HS and HSD models. Statistical tests used were two-way repeated measures ANOVA performed separately on the populations of HS and HSD models, between all modulation frequencies crossed with input location (HS: F(1,15) = 13.55, p<0.001, n = 16; HSD: F(1,15) = 5.027, p=0.017, n = 16; Huynd-Feldt correction reported for both tests). Boxplots denote median of power ratios at the circle; 25th and 75th percentiles are denoted by the extent of the thick coloured bars; full extent of data denoted by thin lines extending from the bars, with outliers shown as coloured open circles. Outliers are defined as points outside of q3 ± 2.7σ(q3 – q1), where q1 and q3 are the 25th and 75th percentiles, respectively (see boxplot function in MATLAB). Stars denote level of significance from Tukey’s post-hoc tests, with p<0.05 (*), p<0.01 (**), and p<0.001 (***). Multiple modulation frequencies sharing the same level of significance are connected with a horizontal bar above. When there are no stars at a particular modulation frequency, this denotes no statistical difference was found between the two populations. If no statistical difference was found across all frequencies, a horizontal bar across all x-axis values is placed with a label of ‘n.s.’ on top, meaning ‘not significant’. All subsequent boxplots in later figures share this design.