(a) Experimental approach for dual labeling from Area X (Dextran-405, cyan) and VTA/SNc (CTB-647, magenta). LC cell bodies depicted in yellow. (b) Injection sites in Area X and VTA/SNc. (c) High power image of retrograde labeling in LC. From left to right: CTB-647 from VTA/SNc, Dextran-405 from Area X, merge, and overlay with DBH. (d) Proportion of retrogradely labeled DBH+ cells that showed dual labeling (grey), or single label from injections in Area X (teal) or VTA (magenta).