Fig. 6: Quantitative analysis of pre- and post-synaptic partner cell type frequencies.
From: Multi-layered maps of neuropil with segmentation-guided contrastive learning
a, The distribution of synapses by predicted inhibitory versus excitatory presynaptic axonal cell type, over the depth of the mouse visual cortex. Lines L1–6 mark the boundaries of the six cortical layers. b, Representative layer 2–3 pyramidal cell. c, Pyramidal cell input synapse locations, annotated (dots) and colored by predicted inhibitory versus excitatory presynaptic partner cell type. d, Distribution of upstream presynaptic partners for layer 2–3 pyramidal cells in V1 with proofread dendrites (n = 69). Each cell is represented by a set of points describing its ratios of input cell types. The mean and standard deviation of the ratios are also shown (darker point and line). UNC refers to synapses for which classification was uncertain. I-UNC refers to synapses for which only a coarse classification (excitatory versus inhibitory) could be made. Error bars are s.d. e, The ratio of thalamocortical to pyramidal innervation onto pyramidal targets in different cortical layers shows major thalamic input to cortical layer 4 (P23, n = 69; P4, n = 23; P5, n = 136; P6, n = 127). Error bars are s.d. f. The thalamocortical synapse counts over the cortical depth. The thalamocortical synapse counts over the cortical depth. Lines L1–6 as in a. g, The thalamocortical synapse count along the lateral axis through the dataset drops at the boundary between V1 and the HVA. The shaded area shows the approximate projection of the V1–HVA border onto the lateral axis. h, As in c, for downstream postsynaptic partners. i, As in d, distribution of downstream postsynaptic partners for layer 2–3 pyramidal cells in V1 with proofread axons (n = 12). P-UNC refers to synapses where SegCLR was not able to classify a pyramidal subtype with sufficient certainty. Error bars are s.d. j,k, Inhibitory versus excitatory balance of downstream postsynaptic partners with increasing distance along P23 axons (n = 12) (j) and P4 axons (n = 19) (k). Mean and s.e.m. are shown for each distance bucket. l, As in k, divided into individual inhibitory subtypes (n = 19). I, inhibitory; P, pyramidal; UNC, uncertain classification. Scale bars: b, 100 μm; c,h, 10 μm.
