On the left is the Eye of Ra associated with the male-related Sun (conscious-self) and connected to the left hemisphere of the brain.
On the right is the Eye of Thoth associated with the female-related Moon (subconscious) and connected to the right hemisphere of the brain.
Its interesting that the ancient Egyptian hieroglyph of the Shen Ring enclosing the red Sun-disk also associated with Ra, is also depicted between the two Eyes of Horus, taking the position of the occultic “third eye” - being also a symbolic depiction of the thalamus.
In these particular iconographies of the Shen Ring, of which the image above is one example, we are being told that the Shen – associated with the Sun and the Infinite Source – also represents the psychic gateway in consciousness.
The Shen Ring is used as a symbol of union and unification and this would be correct in this placement between the two eyes that symbolise the left and right brain opposites.
Its interesting that in the Gardiner Sign list of hieroglyphs, No. S23, for the word dm(dj)-(dmd), is a portrayal of the Shen Ring between two Egyptian whips or flails – meaning “to unite”.
So placed between the two eyes it would mean "to unite the two eyes", or "the eyes are united" as one at the brow.
The Sun disk between the eyes enclosed in a Shen Ring also stands for infinity.
One would interpret that the “Water” hieroglyph at this central location is associated with the ‘womb waters’ of rebirth, which also relates to the symbolic meaning behind the oval Ru hierglyph, which is symbolic of the female vagina-yoni - the birth canal through which onbe is born into the world.
Below is the “Cup” hieroglyph (No. W10 in Gardiner's list), is given the phonetics wsich, sichw – determinative for goblet (jab), and again, in this spiritual, central location between the eyes, the ancient Egyptian cup hieroglyph can only mean one thing, and this may be the origin of the Holy Grail vessel.