Extended Data Figure 4-2

M2/M1 retrogradely labeled cells from the LS, the thalamus (Th), and the pons (Pns). A, Diagram of the experiment to trace corticofugal projections to the thalamus or to the pons leaving collaterals/crossing by the LS. Top left, First retrograde tracer injection (green retrobeads) into the LS. Bottom panels, Second retrograde tracer injection (red retrobeads) into the thalamus or the pons. Top right, Diagram of a sagittal section showing the anteroposterior level of the striatum, the thalamus or the pons (black vertical lines). Bottom right, A coronal diagram illustrating the M2 cortical projection to the LS (green), the thalamus (red), or both (yellow). B, Photomicrographs of the sites of injection of retrobeads into the LS (green) or the thalamus (Th; red) or the pons (Pns; red). C, left panels, green, M2/M1 cortico-striatal cells; red, M2/M1 cortico-thalamic cells. Right panels, Zoom-in from the pink squares on the left. D, Percentage of single target cells and cells reaching either the thalamus or the pons leaving collaterals/crossing at the LS. Green, The proportion of cells only targeting the LS; red, the proportion of cells targeting either the thalamus (top) or the pons (bottom); yellow, the proportion of cells that targeted the LS and the thalamus (top) or the LS and the pons (bottom) simultaneously. Download Figure 4-2, TIF file.