Cell-Type Percolation

Answers the question: Which cell types form one connected structure, and which are split into separate patches?

For each group in the selected annotation, two cells are connected when they are no more than a distance $r$ apart. Connections can form chains: if cell A is connected to B and B to C, all three belong to the same patch. As $r$ increases, smaller patches merge into larger structures.

Map. Each cell is colored by the log10 size of its connected same-group patch at a fixed linking distance. Brighter colors indicate larger patches, darker colors indicate smaller patches, and unpainted cells have no result.

Plot. The x-axis shows the linking distance $r$, normalized by the typical nearest-neighbor distance within each group. The y-axis shows the fraction of the group’s cells contained in its largest connected patch.

Each line represents one group. Curves rising further to the left indicate greater connectivity, while curves rising further to the right indicate greater fragmentation.

Table. The percolation threshold r* is the smallest distance at which the largest patch contains the selected fraction of the group, 50% by default. r*/NN expresses this threshold relative to the group’s own spacing. r*/null compares it with random groups of the same size: values below 1 indicate greater connectivity than expected, while values above 1 indicate greater fragmentation.