Abstract
Though it was definitively recognized over a century ago as an extra cranial nerve in humans, cerebral nerve 0 (CN 0) is still mostly absent from contemporary anatomy textbooks. Since the nerve's fibers were first observed entering the brain in the lamina terminalis of the species under examination, the nerve is known as the nervus terminalis. Since the CN 0 has been shown to secrete luteinizing hormone, it is assumed that the CN 0 is involved in reproductive activity. Because of its connection to the hypothalamic kisspeptin neuronal circuitry, CN 0 raises clinically important issues about the relationship between the system and neuropsychiatric symptoms and disorders, as well as the function of disruptions in this relationship.
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