Fig. 4

a Horizontal projection of 12 SVN reconstructed neurons. Neurons are colorized based on their inferred directional tuning. Polar plot inset shows the directional tuning vectors of each neuron. Gray bar indicates location of coronal plane where axon trajectories are shown in boxed inset. Scale for reconstructions as in c. Electron micrograph (bottom) shows a utricular afferent (pseudocolored green) contacting two dendrites of SVN neurons (yellow). Scale bar, 500 nm. b As in a, for 11 tangential nucleus reconstructed neurons. Sagittal projection inset (bottom) shows the divergence of tangential neuron axons in the dorsoventral axis. c As in a but for 19 VS neurons. d Dendrograms of three example neurons from the SVN, tangential, and VS populations. The soma is represented by a black circle and each dendrite is represented by lines. Gray circles indicate synaptic inputs from utricular afferents, which appear disproportionately concentrated on a small number of dendrites. Axons are truncated for purposes of scale. These and all dendritic arbors are provided in the Source Data file. e Quantification of synaptic clustering, measured as distances between synapses, using three Monte Carlo models compared to actual data. Synaptic locations were modeled as randomly distributed across the arbor (unweighted model), preferentially weighted within 50 µm of afferent axons, or preferentially weighted within 5 µm of afferent axons. The observed level of synaptic clustering is shown in red. See Methods for detailed description.