Parietal eye

A parietal eye (third eye, pineal eye) is a part of the epithalamus in some vertebrates. The eye is at the top of the head; is photoreceptive; and is associated with the pineal gland, which regulates circadian rhythmicity and hormone production for thermoregulation.^[1] The hole that contains the eye is known as the pineal foramen or parietal foramen, because it is often enclosed by the parietal bones.

The parietal eye was discovered by Franz Leydig, in 1872, from work with lizards.^[2]

^ Eakin, R. M (1973). The Third Eye. Berkeley: University of California Press.
^ Eakin, Richard M. (1973), "3 Structure", The Third Eye, University of California Press, pp. 32–84, doi:10.1525/9780520326323-004, ISBN 978-0-520-32632-3, retrieved 2023-03-28

[:0-1] Eakin, R. M (1973). The Third Eye. Berkeley: University of California Press.

[:1-2] Eakin, Richard M. (1973), "3 Structure", The Third Eye, University of California Press, pp. 32–84, doi:10.1525/9780520326323-004, ISBN 978-0-520-32632-3, retrieved 2023-03-28

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