Your pineal gland is here. The pineal gland consist of nerve cells similar to those in the retina nerve if the eye. The retina nerve is inside the eyeball and receives light stimulation which it transmits to the brain.
Interesting, that I wouldn't be surprised if that is what the Eye of Horus was symbolizing. Because, of course the Egyptians knew about the brain. if you look at the medical papyrus, they had an EXTENSIVE knowledge of anatomy and physiology.