brain image drawing(psd/ai) from an existing jpg

drawing of a horizontal view of a brain based on existing jpg. 1. the file(psd/ai) needs to be layered so that I can change thickness/color of line. 2. the drawing doesn't have to include work of the space between edges of [login to view URL] need only drawing of edge of brain image. 3. drawing should be symetric . I suggest that you draw based on left half of the image and copy/paste/rotate to make the right side. 4. drawing should be smoothe looking and embelished. the accurateness isn't required. An approximate, simpler but embelished and smoothe looking version is needed. we don't need very detailed image.