Pontine tegmentum

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Pontine tegmentum
Pons section at facial colliculus.png
Brainstem -- tegmentum not labeled, but is visible near center
Latin tegmentum pontis
NeuroNames hier-548
NeuroLex ID Pontine tegmentum
TA A14.1.05.301
FMA 71108
Anatomical terms of neuroanatomy

The pontine tegmentum is a part of the pons of the brain involved in the initiation of REM sleep. Throughout its entire length, the pons can be divided anatomically into ventral and dorsal pons: Dorsal pons is known as the pontine tegmentum, whilst the ventral pons is known as the basilar pons. Basilar pons may be considered the rostral extension of the ventral medulla oblongata, which contains the corticospinal tract running craniocaudally. Ventral pons is different to ventral medulla in that it contains additional transverse pontine fibres that continues laterally to become the middle cerebellar peduncle, entering the cerebellar cortex. The pontine tegmentum then, can be considered to be the collection of all the nuclei, neuronal and glial substance dorsal to the basilar pons defined above.

It includes the pedunculopontine nucleus and the laterodorsal tegmental nucleus, among others, and is located near the raphe nucleus and the locus ceruleus.

The trapezoid body, involved in binaural hearing, is part of the pontine tegmentum.


In animal studies, lesions of the pontine tegmentum greatly reduce or even eliminate REM sleep. Injection of a cholinergic agonist (e.g. carbachol), into the pontine tegmentum produces a state of REM sleep in cats.

PET studies seem to indicate that there is a correlation between blood flow in the pontine tegmentum, REM sleep, and dreaming.[citation needed]

Pontine waves (P-waves, or ponto-geniculate-occipital waves) are brain waves generated in the pontine tegmentum. They can be observed in mammals, precede the onset of REM sleep, and continue throughout its course. After periods of memory training, P-wave density increases during subsequent sleep periods in rats. This may be an indication of a link between sleep and learning.

See also[edit]

External links[edit]