Spinal Accessory Nerve (CN XI) | Anatomy & Functions

The video tutorial discusses the spinal accessory nerve, also known as cranial nerve 11, which is a motor nerve innervating the trapezius and sternocleidomastoid muscles. It challenges the traditional definition of cranial nerves by explaining that the spinal accessory nerve originates from the spinal cord, not the brain. The nerve ascends through the foramen magnum and exits the cranium via the jugular foramen. The tutorial also covers the clinical implications of damage to this nerve, such as ipsilateral issues in muscle function and atrophy.

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