Tegmentum

Gray712.png

Tegmentum
File:Tegmentum.png Diagram showing the location of the tegmentum in the brainstem
Details
System	Central nervous system
Identifiers
Latin	tegmentum
TA98
TH	{{#property:P1694}}
TE	{{#property:P1693}}
FMA	{{#property:P1402}}
Anatomical terms of neuroanatomy

The tegmentum is a region of the brainstem that is involved in many vital functions. It is located within the midbrain, pons, and medulla oblongata. The tegmentum is a complex structure that contains various nuclei and tracts that are essential for motor control, sensory processing, and autonomic functions.

Structure

The tegmentum is situated between the ventricular system and distinctive basal or ventral structures at each level of the brainstem. It is continuous throughout the midbrain, pons, and medulla oblongata.

Midbrain

In the midbrain, the tegmentum is located between the tectum and the crus cerebri. It contains important structures such as the red nucleus, the periaqueductal gray, and the substantia nigra.

Pons

In the pons, the tegmentum is found between the basilar pons and the fourth ventricle. It includes the reticular formation, which is crucial for maintaining consciousness and arousal.

Medulla Oblongata

In the medulla oblongata, the tegmentum is located between the pyramids and the fourth ventricle. It contains the inferior olivary nucleus and the nucleus ambiguus, among other structures.

Function

The tegmentum plays a critical role in various functions of the central nervous system:

• **Motor Control**: The tegmentum contains pathways that are essential for voluntary and involuntary motor control, including the rubrospinal tract and the reticulospinal tract.
• **Sensory Processing**: It is involved in the processing of sensory information, particularly through the spinothalamic tract and the medial lemniscus.
• **Autonomic Functions**: The tegmentum regulates autonomic functions such as heart rate, respiration, and blood pressure through its connections with the autonomic nervous system.

Clinical Significance

Damage to the tegmentum can result in various neurological disorders. For example, lesions in the midbrain tegmentum can lead to Weber's syndrome, which is characterized by oculomotor nerve palsy and contralateral hemiparesis. Damage to the pons tegmentum can cause locked-in syndrome, a condition where the patient is conscious but unable to move or communicate verbally due to paralysis of nearly all voluntary muscles.

See also

• Brainstem
• Midbrain
• Pons
• Medulla oblongata
• Reticular formation
• Substantia nigra
• Red nucleus