What mom do you know that would give this hand made brain to a daughter for christmas (LOL). Me, anatomist, biologist, science illustrator, nutty person, with a daughter just graduating from Wright State in behavioral sciences.
Real (emptied) chicken egg is the base of this egg head brain sculpture, covered with a very think layer of translucent polymer clay (to give it some stability). The folds in the brain were just made with a long rolled rope of translucent clay (which here certainly is not the highly convoluted brain of a very intelligent human) but is maybe like a mouse or rat. You can still see some relevant convolutions, like the motor and sensory convolutions areas. I made the temporal lobe a little too flat, but it is still identifiable. The fun part was of course cerebellum with its unique surface patterning, convolutions on a different scale.
Olfactory bulbs and nerves and optic nerves are disproportionately large here, just for easy identification. The egg brain can be removed from the stand and turned over where there is the optic chiasm, the there are mammillary bodies, and a pituitary (which would normally have been more hidden in the brain case, but I added here for fun).
Here is a link to read concerning a possible reason for convolutions, and a great video: