Pontine tegmentum

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Brain: Pontine tegmentum
Brainstem -- tegmentum not labeled, but is visible near center
Latin	tegmentum pontis
NeuroNames	hier-548
Dorlands/Elsevier	t_03/12792480

The pontine tegmentum is a part of the pons of the brain involved in the initiation of REM sleep. 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 is part of the pontine tegmentum.

[edit] Function

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  .

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.

[edit] External links

• Atlas of anatomy at UMich n2a3p2
• http://pathcuric1.swmed.edu/PathDemo/cns1/cns1140.htm
• http://isc.temple.edu/neuroanatomy/lab/atlas/panfc/
• http://www.sci.uidaho.edu/med532/pons.htm

v • d • e Brain: rhombencephalon (hindbrain) Metencephalon/ pons Dorsal/ (tegmentum) surface: Locus ceruleus Trigeminal lemniscus (Dorsal trigeminal tract, Ventral trigeminal tract) cranial nuclei: GSA: Principal V/Spinal V - VIII-c (Dorsal, Anterior)/VIII-v (Lateral, Superior, Medial, Inferior) - SVE: Motor V - VII - GSE: VI - GVE: VII: Superior salivary nucleus MLF, III, IV and VI (vestibulo-oculomotor fibers, medial vestibulospinal tract) sensory/ascending: Trapezoid body/VIII - Superior olivary nucleus Inferior cerebellar peduncle (Vestibulocerebellar tract) motor/descending: Apneustic center • Pneumotaxic center (Medial parabrachial nucleus) - Lateral parabrachial nucleus Ventral/ (base) Middle cerebellar peduncles (Pontocerebellar fibers) - Pontine nuclei motor/descending: Corticospinal tract - Corticobulbar tract - Corticopontine fibers Raphe/reticular Reticular formation (Caudal, Oral, Tegmental, Paramedian) • Raphe nuclei (Median) Myelencephalon/ medulla Dorsal surface: Posterior median sulcus - Postero-lateral sulcus - Area postrema cranial nuclei: GVA: VII,IX,X: Solitary/tract • SVA: Gustatory nucleus • GSE: XII  • GVE: IX,X,XI: Ambiguus • SVE: X: Dorsal • IX: Inferior salivatory nucleus - MLF, III, IV and VI sensory/ascending: Gracile nucleus • Cuneate nucleus (Accessory cuneate nucleus) • Sensory decussation  • Medial lemniscus motor/descending: Dorsal respiratory group Ventral motor/descending: Ventral respiratory group - Pyramid (Motor decussation) - Inferior olivary nucleus (Olivocerebellar tract, Rubro-olivary tract) surface: Anterior median fissure - Antero-lateral sulcus - Arcuate nucleus of medulla - Olivary body Raphe/reticular Reticular formation (Gigantocellular, Parvocellular, Ventral, Lateral, Paramedian) • Raphe nuclei (Obscurus, Magnus, Pallidus)