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.
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Which muscles do the accessory nerves XI 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 is the cranial nerve XI?
The accessory nerve, also known as the eleventh cranial nerve, cranial nerve XI, or simply CN XI, is a cranial nerve that supplies the sternocleidomastoid and trapezius muscles. It is classified as the eleventh of twelve pairs of cranial nerves because part of it was formerly believed to originate in the brain.
What does the spinal accessory nerve innervate?
Motor Function The spinal accessory nerve innervates two muscles – the sternocleidomastoid and trapezius.
How do you check cranial nerve 11?
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.
What is CN 11?
The accessory nerve (CN XI) is probably one of the most controversial of the twelve cranial nerves. There is significant dispute throughout the medical literature regarding whether or not the nerve should truly be classified as a cranial nerve.
What is the function of cranial nerve 11?
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.
What is a function of cranial nerve XI?
What is the motor function of accessory nerve XI?
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 does cranial nerve II do?
The optic nerve is the second cranial nerve (CN II) responsible for transmitting visual information. The optic nerve contains only afferent (sensory) fibers, and like all cranial nerves is paired.
What happens if cranial nerve XI is damaged?
Supranuclear lesions of the eleventh nerve cause moderate, often transient, impairment of function of the sternocleidomastoid and trapezius muscles, due to the bilateral innervation. In the spinal cord the nuclei can be involved in amyotrophic lateral sclerosis, syringomyelia, polio, and intraspinal tumors.
How do you test cranial nerve 11?
What is the main function of 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 is cranial nerve II?
What muscles does cranial nerve 3 innervate?
Cranial nerve III has somatic and autonomic functions. Somatic nerves are homologous with ventral roots of spinal nerves. They originate from the basal plate and innervates the superior rectus, inferior rectus, medial rectus, and inferior oblique muscles. These muscles derive from the first preoptic myotome.