Spatial patterns of excitatory inputs are similar across different types of ganglion cells.

<p>(A) The distribution of intervals between puncta. In the total distribution of intervals, it appears that all eight types of ganglion cells have their highest frequency at about 1–2 µm. The actual distribution of PSD95 puncta is compared with the distribution of the same number of puncta on that same dendritic structure at random (dotted lines). (B) The distribution of nearest-neighbor puncta distance. It is apparent that the excitatory synapses are excluded from a reference synapse site at the distance around 1–2 µm for all ganglion cell types. (C) The density of excitatory synaptic inputs as a function of dendritic branch order. In general, there are few synaptic inputs on the first several orders (or, the proximal zone of the dendritic field), and then the linear density of puncta gradually increases and reaches a plateau in the distal zone of the dendritic field in some but not all ganglion cell types. (D) The density of excitatory synaptic inputs as a function of distance from the soma (or, the Sholl analysis). For all cell types, the linear density of puncta near the soma is low. However, the puncta density, once outside the proximal zone, is relatively homogenous across the dendritic field in some but not all ganglion cell types. Note if more than one cell of a cell type has been sampled, the average value is plotted, but the error bar has been omitted for clarity.