## Chapter 12/Figure 3.gif Back | Home | Next | Slice data: Outlined Regions: Embedded Fibers The top panel indicates (in overlay) the approximate location of the source ("VB", lower center) and target ("Layer IV", upper right) regions used in these simulations. VB was carved out of the raw data by drawing a boundary in one section and propagating the contour to all sections containing the nucleus. Layer IV was defined by eroding the brain surface (in 3D) to two levels, roughly defining the top and bottom of layer IV (but also including some of layer V), and then restricting the cortical region to that sector lying directly above the radiations. The bottom panel shows portions of the paths (crossing this section) taken by simulated axons, en route between these two regions, as they cross the plane of this section. For the most part axons travel along the dark channels in the radiations. Some errant fibers cross the dark fimbria of the Hippocampus. Fragments of these axons' terminal arbors (intact in 3D) are visible in the cortical target zone.