Figure 7.

Sublayer-specific patterns of synaptic connectivity at the branch level with Peters' rule. A, Scatter plots (left) show the branch-level structure of connectivity (R² value) given Peters' rule applied to neurons located in different hippocampal strata. Dots represent individual neurons. A summary of R² values of individual neurons subclassified by layer and sublayer populations is also shown (right). Significant differences in R² values with Peters' rule between deep and superficial subpopulations were observed in PCs but not in PVs. Red +p < 0.05, Conover–Iman scale test for scale (right); n.s., not significant. B, For subpopulations of PCs and PVs in deep and superficial sublayers, a summary of R² values with Peters' rule (deep: **p < 0.01, ****p < 0.0001, permutation test for mean; red +p < 0.05, Conover–Iman scale test for scale; superficial: **p < 0.01, ****p < 0.0001, permutation test for mean; red ++p < 0.01, Conover–Iman scale test for scale) and stacked bar plots of the percentages of highly structured, moderately structured, and nearly random neurons as classified by R² value with Peters' rule. C, A Summary of opposite changes in R² with Peters' rule. Dots represent individual neurons, and solid lines indicate mean R² with Peters' rule; overlaid dashed lines indicate the mean R² with the dendritic-surface-only random model. ****p < 0.0001, permutation test; red +++p < 0.001, red ++++p < 0.0001, Conover–Iman scale test (left). Bar plots show the percentages of highly structured, moderately structured, and nearly randomly structured neurons as classified by R² value; the results show that most PCs are highly structured, whereas more PVs are nearly random, compared with the dendritic-surface-only random model shown in Figure 4A. ****p < 0.0001, Fisher's exact test (right).