Vision and Breathing

Something that most people don’t appreciate is that the eyes are actually two pieces of brain. They are not connected to the brain; they are brain. During development, the eyes are part of the embryonic forebrain. Your eyes get extruded from the skull during the first trimester, and then they reconnect to the rest of the brain. So they’re part of the central nervous system.

https://www.scientificamerican.com/article/vision-and-breathing-may-be-the-secrets-to-surviving-2020/