Figure 2

(A): Schematic showing the branching angles measured between sibling segments, according to two schemes: standard and inverse branch orders. (B): Example of the distribution of angles for standard branch order 1 coming from basal dendritic trees of pyramidal neurons in M2 area. The (upper) rose diagram shows the proportion of data in each interval of angles (in degrees). The (lower) density plot shows the empirical histogram of the dataset (bars) and the fitted von Mises density (thick black line). The dataset is shown with green crosses below the histogram. (C): The proposed circular boxplots of the angles showing the summary statistics of a dataset as arcs inside a circle, for standard (upper diagram) and inverse (lower diagram) branch orders. A black dot represents the median of the dataset, whereas the colored thick lines (same color code as in A) extend from the lower quartile (Q1) to the upper quartile (Q3). The black lines extend from the minimum to the maximum values in the dataset included in the interval [Q1 − 1.5·IQR, Q3 + 1.5·IQR], where IQR = Q3 − Q1 is the interquartile range. The small colored dots indicate data values that are not in this interval and are considered as outliers (see Supplementary Figure S1 for further details). (D): Test-based diagrams illustrating the pairwise comparisons of the mean angles from datasets shown in (C). Two nodes (representing two datasets) are connected when the hypothesis of equal mean angles of the corresponding datasets using Watson test cannot be rejected. Two nodes are not connected if the mean angles were deemed significantly different. See Supplementary Tables 6–7 (standard) and 10–11 (inverse) for further details on statistical tests. (E): Circular boxplots coming from basal dendritic trees of pyramidal neurons from M2 region, grouped according to their branch complexity (same color code as in A). Test–based diagrams are presented next to each graph to show comparison results between mean angles of different branch orders. See Supplementary Tables 8–9 and 12–13 for further details on statistical tests and Supplementary Figures S2–S4 for the corresponding diagrams of the remaining cortical regions examined (M1, S1, S2, V1, V2 and PrL). O1–O4: standard branch order 1–4; O1′–O4′: inverse branch order 1–4.