Supplementary Figure 8: Spatial resolution of DMD-based optogenetic mapping and input maps of L5 FS neurons

a, Left: schematic of DMD-based setup for photo-stimulation. Right: Example spike probability maps of an example excitatory neuron in L5, L4, and L2/3. b, Spatial resolution of light-evoked spiking in ChR2⁺ excitatory neurons in the emx1-Cre line. c, Plot of spike probability vs. distance of the photo-stimulation light from the soma of the recorded neuron. d, As in c) but for mean number of action potentials evoked per photo-stimulation trial. e, Scatter plot of the mean excitatory input of recorded L5 FS neurons comparing input from L4 and L5. f, Top: All 31 excitatory input maps of L5 FS neurons ranked ordered according to the ratio of their mean excitatory input from L4 to L5. Maps have been rotated and cropped to show only the region corresponding to the barrel column in which each FS cell was located. White lines correspond to the upper and lower borders of L4. Green and white dots indicate the soma location of the recorded cell. Bottom: Corresponding log value of the ratio of mean charge transfer per unit area of L4 to mean charge transfer per unit area of L5 for each map. g, As in top panel of f), but with each map normalized to its range. h, Left: Average excitatory input map for all L5 FS cells (n = 31 cells in 26 slices from 13 mice), after aligning the barrel of the home column of each recorded cell. Right: As in left panel, but after horizontally aligning maps to the soma of each recorded cell. Scale bar: 200 μm. i, Quantification of the proportion of excitatory charge transfer to L5 FS cells originating from within the home column versus surrounding columns across cortical layers, normalized to total charge transfer in each map.