Kinda makes me wonder how the Egyptians knew that this was important, that and also an "eye". Being your third eye anyway.
My thoughts: The only thing that is a Pineal Gland in that picture is the little nodule underneath the "45". In fact if you look up surgical pictures of pineal glands . . . (Pineal Gland is #1) . . .you'll see 99.99% of them look nothing like the Eye of Horus (not Ra), this is all about angle. Also I'm not sure what you're implying here, about the concepts of "third eye" and "eye of horus": "The Eye of Horus is an ancient Egyptian symbol of protection, royal power and good health." To go another step and assume that egyptians somehow knew about the pineal gland and that this all ties together with everything else . . . . eh. Sorry, I'm all for seeing the everything in everything, but only when it's actually there . You've found a visual similarity between a particular photograph of human anatomy and an egyptian symbol, but that similarity is visual, you can't automatically assume it is semantic, and in this case, you should have major critical thinking alarm bells going off if you start to assume too much about ancient egyptians from an internet picture of the human brain. Buzzkill complete.