Perihypoglossal nuclei

Perihypoglossal Nuclei

The Perihypoglossal Nuclei are a group of nuclei in the medulla oblongata that are involved in the control of tongue movements. They are located near the hypoglossal nucleus, hence the name 'perihypoglossal'.

Anatomy

The perihypoglossal nuclei consist of three distinct nuclei: the intercalated nucleus, the prepositus nucleus, and the nucleus of Roller. These nuclei are located in the medulla oblongata, near the midline, and are closely associated with the hypoglossal nucleus.

Intercalated Nucleus

The intercalated nucleus is the smallest of the three perihypoglossal nuclei. It is located medial to the hypoglossal nucleus and is involved in the coordination of tongue movements.

Prepositus Nucleus

The prepositus nucleus is located lateral to the intercalated nucleus. It plays a role in eye movements by integrating information from the vestibular system and the cerebellum.

Nucleus of Roller

The nucleus of Roller is the largest of the perihypoglossal nuclei. It is located posterior to the hypoglossal nucleus and is involved in the control of tongue movements.

Function

The perihypoglossal nuclei are involved in the control of tongue movements. They receive input from the cerebral cortex and the cerebellum, and send output to the hypoglossal nerve, which innervates the muscles of the tongue.

Clinical Significance

Damage to the perihypoglossal nuclei can result in dysarthria, a motor speech disorder characterized by poor articulation of phonemes. In severe cases, it can lead to anarthria, a complete inability to produce speech.

See Also

• Medulla oblongata
• Hypoglossal nucleus
• Hypoglossal nerve
• Tongue