What is the tectum and tegmentum?
The region of the midbrain posterior to the cerebral aqueduct is called the tectum, which means “roof” in Latin. The tectum consists primarily of the superior and inferior colliculi. The area of the midbrain anterior to, or in front of, the cerebral aqueduct is called the tegmentum.
What are the parts of the tegmentum?
The tegmentum is located in front of the tectum. It consists of fibre tracts and three regions distinguished by their colour—the red nucleus, the periaqueductal gray, and the substantia nigra.
What structures are rostral to the midbrain?
The principal regions of the midbrain are the tectum, the cerebral aqueduct, tegmentum, and the cerebral peduncles. Rostrally the midbrain adjoins the diencephalon (thalamus, hypothalamus, etc.), while caudally it adjoins the hindbrain (pons, medulla and cerebellum).
What is midbrain tegmentum?
The tegmentum (from Latin for “covering”) is a general area within the brainstem. The tegmentum is the ventral part of the midbrain and the tectum is the dorsal part of the midbrain. It is located between the ventricular system and distinctive basal or ventral structures at each level.
What is posterior to tegmentum of midbrain?
The posterior surface of the midbrain is called the tectum, or roof, of the midbrain. The tectum features four tubercles on its surface which lie inferior to the pineal gland. The upper pair of tubercles are the left and right superior colliculi, while the lower pair are the left and right inferior colliculi.
What is the function of tegmentum?
Tegmentum. Reticular formation: This highly diverse and integrative area contains a network of nuclei responsible for many vital functions including arousal, consciousness, sleep-wake cycles, coordination of certain movements, and cardiovascular control.
What is the difference between the midbrain tectum and tegmentum?
(Tegmentum not labeled, but surrounding structures more clearly defined.) The midbrain is anatomically delineated into the tectum (roof) and the tegmentum (floor). The midbrain tegmentum extends from the substantia nigra to the cerebral aqueduct in a horizontal section of the midbrain.
What adjoins the midbrain in the rostral direction?
Rostrally the midbrain adjoins the diencephalon ( thalamus, hypothalamus, etc.), while caudally it adjoins the hindbrain ( pons, medulla and cerebellum ). In the rostral direction, the midbrain noticeably splays laterally.
What is the mesencephalic tegmentum?
The mesencephalic tegmentum, also known as the pretectum, is the central part of the midbrain. It contains the reticular and cranial nerve nuclei, as well as several neural pathways. These structures span on various levels of the midbrain, so let’s analyze their anatomy and location.
What does the rostral medullary medial tegmentum target?
The rostral medullary medial tegmentum including the RMg targets mainly laminae I and V neurons in the dorsal horn throughout the length of the spinal cord (Fig. 36.9, left). These pathways represent direct inhibitory connections with neurons in turn projecting to supraspinal levels ( Antal et. al., 1996; Light et. al., 1986 ).