What does the cranial nerve 11 innervate?
The muscles innervated directly by the XI nerve are the trapezius and the sternocleidomastoid, in addition to the laryngeal musculature (in collaboration with the vagus nerve), such as the palatal, pharyngeal, laryngeal muscles.
Where are the nuclei of the cranial nerves located?
The cranial nerve nuclei are horizontal structures spread out in the midbrain (III, IV), the pons (V, VI, VII, VIII), and the medulla (IX, X, XI, XII).
Where does cranial nerve 11 originate from?
The accessory nerve emerges from the medulla of the brainstem, and is visible at the bottom of the image in blue. The accessory nerve is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles.
Which two structures does cranial nerve XI live between?
The accessory nerve provides motor function (movement) to two muscles essential to neck and shoulder movement, the sternocleidomastoid (SCM) and the trapezius, as well as to the larynx (voice box) and other structures in the throat. It’s the 11th of the 12 cranial nerves and is often referred to as CN XI.
Is cranial nerve 11 sensory or motor?
Cranial nerves I, II, and VIII are pure sensory nerves. 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.
How do you assess 11 cranial nerves?
The 11th (spinal accessory) cranial nerve is evaluated by testing the muscles it supplies: For the sternocleidomastoid, the patient is asked to turn the head against resistance supplied by the examiner’s hand while the examiner palpates the active muscle (opposite the turned head).
What is the cranial nerve nuclei?
The cranial nerve nuclei are a series of bilateral grey matter motor and sensory nuclei located in the midbrain, pons and medulla that are the collections of afferent and efferent cell bodies for many of the cranial nerves.
How many nuclei are in the cranial nerve?
The sixteen cranial nerve nuclei can be most easily remembered if they are assembled into functional groups and anatomical location (Table A3—from Purves et al., Neuroscience, 6th Ed.; Figure 4.2).
What is the 11th 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. The spinal part supplies innervation to the Sternocleidomastoid and Trapezius muscles.
How many nuclei does the accessory nerve have?
The upper five spinal cord segments house the nucleus of the accessory nerve….Embryology of the accessory nerve.
|Divisions (parts)||Cranial division and spinal division|
Are cranial nerves myelinated?
The optic nerve is the only cranial nerve to be myelinated by oligodendrocytes. The trigeminal nerve will be myelinated by Schwann cells.
Is cranial nerve 11 motor or sensory?