What is associated with the tectum and the tegmentum?
The tegmentum is the ventral part of the midbrain and the tectum is the dorsal part of the midbrain. It forms the floor of the midbrain (mesencephalon) whereas the tectum forms the ceiling. It is a multisynaptic network of neurons that is involved in many subconscious homeostatic and reflexive pathways.
What runs through the crus cerebri?
Terminology. The crus cerebri (cerebral crus) usually refers to the most anterior, semilunar shaped bundle of white matter fibers in the midbrain, including the corticospinal tract centrally (3/5 intermediates) as well as the corticopontine (fronto-pontine and temporo-pontine fibers) and corticobulbar tracts.
What does the tegmentum contain?
The tegmentum of the medulla contains the medullary reticular formation, together with cranial nerve nuclei and ascending tracts. It also includes a number of ‘vital centres’ which subserve cardiorespiratory functions and airway-protective reflexes (e.g. cough, sneeze, gag).
What is the meaning of tegmentum?
Definition of tegmentum : an anatomical covering : tegmen especially : the part of the ventral midbrain above the substantia nigra formed of longitudinal white fibers with arched transverse fibers and gray matter.
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 tectum of the midbrain?
Anatomically, the tectum is that portion of the mesencephalon, or midbrain, sitting between the hindbrain and the forebrain. The name is the Latin word for roof and reflects the view of early anatomists that the tectum formed a roof over the fluid-filled cerebral aqueduct and the tegmentum.
What is tectum in pollen grain?
Tectum is a term used to describe a structure resembling a roof. Tectum is also used to refer to the roof-like protrusions on the outer surface of a pollen or a spore. When a pollen grain has tecta on its outermost layer, it is described as tectate. When there are no tecta, the pollen is described as intectate.
What is crus cerebri function?
In human nervous system: Pons. These massive crossed fibres, called crus cerebri, form the middle cerebellar peduncle and serve as the bridge that connects each cerebral hemisphere with the opposite half of the cerebellum. The fibres originating from the cerebral cortex constitute the corticopontine tract.
What happens if the tegmentum is damaged?
The brainstem tegmentum, including the reticular formation, contains distinct nuclei, each of which has a set of chemical, physiological and anatomical features. Damage to the brainstem tegmentum is known to cause coma, the most radical disturbance of consciousness.
Where is the tegmentum located in the brain?
The tegmentum is one of the areas of the brainstem. It is a phylogenetically old part of the brainstem and, in adults, is the location of the brainstem nuclei. In the midbrain, it sits between the quadrigeminal plate and cerebral peduncles.
Is the tectum part of the cerebral aqueduct?
The small portion of the midbrain dorsal (=posterior) to the cerebral aqueduct is the tectum or roof plate. It bears the superior and inferior colliculi (which are concerned with visual and auditory reflexes respectively). The remainder of the midbrain is made up of the cerebral peduncles.
When does infarction or lesion affect the tegmentum?
When the infarction or lesion affects the tegmentum, the clinical signs will depend on the cranial nerves affected. A patient could present with the inability to abduct the eye laterally due to ischaemic injury to CN VI or exhibit loss of dorsal column modalities on the contralateral side due to medial lemniscus damage.
Where is the tegmentum located in the pons?
In the pons, it is posterior to the basilar part of the pons and, in the medulla is adjacent to the pyramids. Tegmentum originates from the Latin for covering.