Figure 5.

mPPC projections to frontal midline cortex. Anterogradely labeled fibers in the frontal midline cortex resulting from an injection of PHA-L in mPPC. (A–F) Coronal sections arranged from rostral (A) to caudal (F). Solid lines indicate borders between cortical areas and dashed lines demarcate cortical layers. Insets in all panels indicate the rostrocaudal position of the section and the approximate area shown. Densest labeling was seen in area cM2. (G) PHA-L injection site in mPPC shown as a filled circle in a surface rendering of the brain and all injection sites. (H) Drawing of the injection site in a coronal section with the borders of mPPC indicated by solid lines. (I) Intensity representation of the density of labeling in frontal midline areas from rostral to caudal (R–C), Lighter color indicates a denser plexus of labeled fibers. The scale bar relates the color code in the flatmaps to the density scores initially assigned to each pixel in the digitized sections (for details, see “Materials and Methods” section). Bregma is indicated by an orange dot and the genu of the corpus callosum, which coincides with the border between rM2 and iM2, by a green dot. Scale bar: 500 μm.