Accessory Nerves

The 11th Cranial Nerve. The accessory nerve originates from Neurons in the medulla and in the cervical spinal cord. It has a cranial root, which joins the vagus (10th cranial) nerve and sends motor fibers to the Muscles of the Larynx, and a Spinal Root, which sends motor fibers to the trapezius and the sternocleidomastoid Muscles.