Fig. 1. Comparative morphology and regional variability in human and mouse cerebellar PCs.

(A) Immunolabeling of PCs in humans reveals a range of dendritic morphologies, categorized by primary dendrite geometry as Normative, Split, or Poly. (B) Human mid-hemisphere reconstruction demonstrating the spatial distributions of each morphological type. As a result of variable preservation of tissue some anterior lobules and intervening posterior sublobules had a lower density of labeled PCs. (C) Morphology demographics across lobules (n = 3 individuals >86 years old, 6640 cells; see table S1). (D) PCs filled with dye during a patch experiment in mice to scale with human cells also exhibit Normative, Split, and Poly morphology. (E and F) as in (B and C), but in mice (n = 3 mice >P50, 1350 cells; see table S2). (G) Morphological category distribution counted by lobule (top) in human (n = 20, 21, and 21 lobules) and mouse (n = 30, 30, 29) reveals a consistent increase in the number of Split and Poly PCs in human matching the rates of the whole cell population (bottom). Average lines depict median lobule value. *P < 0.05, **P < 0.01, ***P < 0.001.