Pons

 
Pons audio    More

The pons is found only mammals and it seems to be responsible for learned coordination and balance as opposed to unlearned coordination which are basically instinctual.  The coordination which the pons helps to integrate are from the learned areas of the cerebral cortex. The tract runs from the cerebral cortex down to the cerebellum with synapses in the pons. The tract begins as the corticopontine tracts which then proceeds to the deep cerebellar nuclei. All the lobes of the cerebral cortex contribute to this. They include

bullet

Frontopontine

bullet

Temporopontine

bullet

Occipitopontine

bullet

Parietopontine

The whole tract beginning from the cortex and ending in the cerebellum after relaying in the pons may then be called corticopontocerebellar tract and they relay in the ventral aspect of the pons in the basis pontis.

Pons is therefore divided into the following parts

bullet

Basis pontis ( most ventral)

bullet

Pontine tegmentum which contains nuclear groups of cranial nerves V, VI, VII. It also contains the reticular formation of the pons.

bullet

Isthmus rhombencephali is the most rostral of the pons which joins the midbrain.

 The most dorsal part of the pons is the fourth ventricle. The floor, which is part of the so-called rhomboid fossa because it is pyramidal in shape, contains the following structures

bullet

Facial colliculus, this is the swelling which has the abducent nucleus and also the internal genu of the facial nerve.

bullet

It also has the rostral extreme of the tuberculum acousticum. It is separated from the back of the medulla by striae medullaris.

Axial MRI showing pons

 

Practical (Pal-Weigert)


Brain short movie

 

Pons

  Corticopontocerebellar tract

  Basis pontis

  Pontine tegmentum

     Nuclear groups of cranial nerves

     Cranial nerve root/nuclei of pons

     Pontine reticular formation

        Nucleus reticularis pontis pars oralis

        Nucleus reticularis pontis pars caudalis

        Nucleus reticularis pontis pars interpolaris

   Vestibular area

  Vestibular nucleus

  Facial colliculus

  Internal genu of the facial nerve

  Tuberculum acousticum

  Abducent nucleus

   Parabducent nucleus

  Facial nerve in pons

     Facial nucleus

  Trigeminal nerve in pons   

      Sensory (pontine) nucleus of V

     Motor nucleus of V

      Spinal nucleus of V

       Mesencephalic of V

  Trapezoid body

  Superior olive

  Medial lemniscus

  Lateral lemniscus

  Medial longitudinal fasciculus

  Nucleus reticularis pedunculopontinus

  Isthmus rhombencephali

     Locus ceruleus

  Superior medullary velum

 

 

 

Electronic School of Medicine
Creator: Oluwole Ogunranti

 

 
 
Pons in Scene 5 DIGITAL LOCATOR OF PONS:  Scene 1-Brain -inferior surface. Scene 2 Expand brainstem. Scene 3, Brain -medial view. Scene 4 Remove midbrain. Scene 5 Display mid sagittal section of brainstem. Rollover mouse to label and click to display page, Click blinking end page to display pons page.

 
Brainstem Medulla Pons Midbrain Thalamus Epithalamus
Basal ganglia Forebrain Temporal lobe Cerebral operculum Remove operculum Wall of lateral ventricle 1
Wall of lateral ventricle 2 Wall of lateral ventricle 3 lateral ventricle 1 lateral ventricle 2 Base of brain Rhomboid fossa

Roll over mouse to label
 
Pons- front Pons - back

 

 

 

 

 
Pons and MRI

 

 

 

Items
Cell Biology
Histology
Embryology

Gross anatomy
Lymphatic drainage
Organ integration
Clinical anatomy

Quiz

Dissector

Physiology

Biochemistry

Chemical Pathology

Anatomical Pathology

Imaging

Medicine

Psychiatry

Surgery

Pontine clinical anatomy
Embryology
MRI

Physiology

Pontine diseases
Brain assembler

Main Subject Course Links

eAnatomy eAnesthesia eBiochemistry eChemical pathology eCommunity Health
eDermatology eENT eGynecology eHematology eImaging
eMedicine eMedical microbiology eObstetrics eOphthalmology ePathology
ePediatrics ePharmacology ePhysiology ePsychiatry    eSurgery/eOrthopedics
eLab eOSCE eProcedures eInvestigations eSchool/Videopage
eOrgans eLocator Anatomy Museum eDissector eFractures/Dissect-it-yourself
All diseases eClerking eTreatment eDoctor ePatient