XII PAR CRANEAL. NERVIO HIPOGLOSO

Summary

This video dives into the anatomy and function of the hypoglossal nerve, which controls the muscles of the tongue, excluding the palatoglossus. Originating from the motor nucleus in the medulla oblongata, the nerve emerges from the skull and travels through various regions, supplying motor and sensory fibers to the tongue and surrounding muscles. The video also highlights the nerve's branches, including the meningeal branch, cervical roots, and branches to the styloglossus and genioglossus muscles. With a fun twist, the video ends by encouraging viewers to try rolling their tongues into a taco shape, showcasing the complexity behind this simple action.

Q & A

What is the hypoglossal nerve responsible for?

The hypoglossal nerve is responsible for innervating the muscles of the tongue, except for the palatoglossus muscle.

Where does the hypoglossal nerve originate?

The hypoglossal nerve originates in the motor nucleus of the 12th cranial nerve, located in the dorsal part of the medulla oblongata.

What is the hypoglossal nerve's apparent origin?

The hypoglossal nerve's apparent origin is the preolivary sulcus, located between the pyramid and the olive of the medulla oblongata.

What is the function of the fibers in the hypoglossal nerve?

The fibers in the hypoglossal nerve carry motor and somatic general information, specifically for skeletal muscles.

How does the hypoglossal nerve exit the skull?

The hypoglossal nerve exits the skull through the hypoglossal canal and receives a branch from the cervical plexus as it does so.

What does the cervical plexus contribute to the hypoglossal nerve?

The cervical plexus contributes motor fibers from the C1 and C2 spinal nerves and sensory fibers from the C2 spinal nerve's ganglion.

Where does the hypoglossal nerve travel after exiting the skull?

After exiting the skull, the hypoglossal nerve descends, positioned medially to the internal jugular vein and laterally to the internal carotid artery, eventually passing deep to the submandibular gland and ascending towards the tip of the tongue.

What are the branches of the hypoglossal nerve?

The hypoglossal nerve gives off several branches, including the meningeal nerve, the superior root of the cervical loop, the nerve to the thyrohyoid muscle, the nerve to the styloglossus muscle, and the nerve to the genioglossus muscle.

What is the role of the meningeal branch of the hypoglossal nerve?

The meningeal branch has a recurrent path towards the skull and the dura mater of the posterior cranial fossa, and its fibers originate from the spinal ganglion of the C2 nerve.

What is the function of the superior root of the cervical loop?

The superior root of the cervical loop, or descending branch, helps form the cervical loop and primarily carries motor fibers from C1 and C2 spinal nerves to muscles of the infrahyoid region.

What is the significance of the hypoglossal nerve in performing complex tongue movements?

The hypoglossal nerve plays a key role in complex tongue movements, such as rolling the tongue into a taco shape, which involves precise muscle control within the tongue, facilitated by this nerve.