Fig. 4: Unsupervised exploration of mouse layer 5 pyramidal dendrite embeddings.

a, SegCLR embeddings projected to 3D UMAP space, with two selected axes displayed. Each point represents an embedding (aggregation distance 50 μm) sampled from only the dendrites of mouse layer 5 pyramidal cells. The UMAP data separate into three main clusters. b, Renderings of selected cells, colored to match a for locations for which the nearest embedding fell within cluster 1 (blue) or cluster 2 (red). Projections falling within cluster 1 are strongly associated with the apical dendrite subcompartment, while cluster 2 is strongly associated with a subset of basal dendrites corresponding to cells with a distinct ‘near-projecting’ (NP) morphology (inset). c, Of the cells for which the projections fall within cluster 3, a subset have distinctive axon trajectories consistent with their axons joining a major output tract (left). These ‘tract’ cells also occupy a distinct subregion within cluster 3 (middle, green). Cells occupying the remainder of cluster 3 (middle, purple) consistently lack the axon tract morphology (right). The tract and no-tract groups are also able to be separated in both primary visual area V1 (left group of cells for both tract and no-tract) and higher visual areas (right group of cells for both tract and no-tract). Scale bars, 100 μm.