Which is the 11th cranial nerve?
Spinal Accessory Nerve
The Spinal Accessory Nerve (SAN) or Cranial Nerve 11 is termed a cranial nerve as it was originally believed to originate in the brain. It has both a cranial and a spinal part, though debate still rages regarding if the cranial part is really a part of the SAN or part of the vagus nerve.
What does cranial nerve number 11 do?
This nerve supplies the sternocleidomastoid and trapezius muscles, which have the following functions: Rotation of head away from the side of the contracting sternocleidomastoid muscle. Tilting of the head toward the contracting sternocleidomastoid muscle. Flexion of the neck by both sternocleidomastoid muscles.
How do you assess 11 cranial nerves?
CN 11 is tested by asking the patient to shrug their shoulders (trapezius muscles) and turn their head (sternocleidomastoid muscles) against resistance. The 12th CN is tested by having the patient stick out their tongue and move it side to side.
Is cranial nerve 11 sensory or motor?
Cranial nerves III, IV, VI, XI, and XII are pure motor nerves. Cranial nerves V, VII, IX, and X are mixed sensory and motor nerves. The olfactory nerve (CN I) contains special sensory neurons concerned with smell. The optic nerve (CN II) contains sensory neurons dedicated to vision.
What muscles does cranial nerve 11 innervate?
It innervates both the trapezius and the sternocleidomastoid muscles.
Where does cranial nerve 11 exit the skull?
the jugular foramen
It leaves the cranium via the jugular foramen, where it briefly contacts the spinal part of the accessory nerve. Immediately after leaving the skull, cranial part combines with the vagus nerve (CN X) at the inferior ganglion of vagus nerve (a ganglion is a collection of nerve cell bodies).
Where does the accessory XI nerve originate?
The cranial root of the accessory nerve originates from cells located in the caudal medulla. They are found in the nucleus ambiguus and leave the brainstem with the fibers of the vagus nerve.
What is CN III?
The oculomotor nerve (the third cranial nerve; CN III) has three main motor functions: Innervation to the pupil and lens (autonomic, parasympathetic) Innervation to the upper eyelid (somatic) Innervation of the eye muscles that allow for visual tracking and gaze fixation (somatic)
What are the 10 spinal nerves?
Types and Functions of Spinal Nerves
- Cervical Nerves.
- Thoracic Nerves.
- Lumbar Nerves.
- Sacral Nerves.
- Coccygea Nerves.
What is the name of 12 cranial nerve?
In higher vertebrates (reptiles, birds, mammals) there are 12 pairs of cranial nerves: olfactory (CN I), optic (CN II), oculomotor (CN III), trochlear (CN IV), trigeminal (CN V), abducent (or abducens; CN VI), facial (CN VII), vestibulocochlear (CN VIII), glossopharyngeal (CN IX), vagus (CN X), accessory (CN XI), and …
Are there 12 or 13 cranial nerves?
Your cranial nerves are pairs of nerves that connect your brain to different parts of your head, neck, and trunk. There are 12 of them, each named for its function or structure.
What happens if the spinal accessory nerve is damaged?
The spinal accessory nerve originates in the brain and enables motion in the trapezius and sternomastoid muscles in the neck. A spinal accessory nerve injury can be caused by trauma or damage during surgery, resulting in shoulder pain, “winging” of the shoulder blades and weakness of the trapezius muscle.
What are the 12 nerves of the body?
Cranial nerve function
- I. Olfactory nerve. The olfactory nerve sends sensory information to your brain about smells that you encounter.
- II. Optic nerve.
- III. Oculomotor nerve.
- IV. Trochlear nerve.
- V. Trigeminal nerve.
- VI. Abducens nerve.
- VII. Facial nerve.
- VIII. Vestibulocochlear nerve.