This is an illustration of deep brain stimulation for the treatment of major depression. This procedure is currently under investigation by Helen Mayberg, MD, who was an advisor for this piece. The electrode stimulates the intersection of the cingulum, forceps minor, and uncinate fasciculus, near Broadmann's area 25. 

I used real brain imaging to give me a base for the model in ZBrush, did some sculpting in there by hand as well, as well as much of the painting of the brain. The tracts were done in Zbrush, with a little Photoshop on the back end to bring out some of the individual fibers a little more. The ghosting was accomplished by rendering several passes out of ZBrush and compositing them and hand-paining the ghosted out areas in Photoshop. 

ZBrush, Cinema 4D, and Photoshop. ©Emory University 2014.