Interesting facts about the oculomotor nerve: Each cranial nerve splits into two branches. One branch transmits messages to the right side of your body and the other to the left.

This long nerve makes up 3/4 of the nerve tissue in your parasympathetic nervous system. In fact, the vagus nerve is the longest of any of the 12 cranial nerves.

The vagus nerve, or cranial nerve 10, serves as a main communication channel between your gut and brain. Learn about its function, location, how to stimulate it, and more.