Fig. 4: Co-aligned visual and tactile anatomical projection maps in the dorsal cortex.

a Schematic of the data collection and analysis pipeline for topographic anatomical tracing. b Anterograde labeling of S1 projections using injections of viral vectors AAV-CAG-GFP and AAV-CAG-tdTomato. Left: injection sites in B2 and C2 barrels in whisker S1. Right: conserved somatotopic organization of projections in associative areas for the cortex shown on the left (top). Bottom: Reconstructed whisker preference averaged across mice using all injection sites depicted by circles (see “Methods”, N = 9 mice and n = 18 injections, Pearson coefficient of correlation between anatomical and wide-field map: 0.8311, two-sided t test p < 10^–300). c Same as panel b but for anterograde labeling of V1 projections with two injection sites along the iso-horizontal axis (N = 7 mice and n = 14 injections, Pearson coefficient of correlation: 0.5121, two-sided t test p < 10^–300). d Retrograde labeling of S1-projecting neurons using CTB-Alexa 555 and CTB-Alexa 647 injections. Top: Examples of CTB-labeled neurons spatially organized in associative areas. Bottom: Reconstructed map of preferred whisker in projecting neurons over the dorsal cortex combining all injection sites (N = 5 mice and n = 8 injections, Pearson coefficient of correlation: 0.663, two-sided t test p < 10^–300).