Brain: Pons
Diagram showing the positions of the three principal subarachnoid cisternæ. (Pons visible at center. )
Anteroinferior view of the medulla oblongata and pons. In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species
Gray's	subject #187 785
Part of	Brain stem
Artery	pontine arteries
NeuroNames	hier-538
MeSH	Pons

The pons (sometimes pons Varolii after Costanzo Varolio) is a structure located on the brain stem. Costanzo Varolio, latinized as Constantius Varolius, (born Bologna, 1543 - died Rome, 1575) was an Italian anatomist and a papal The brain stem (or brainstem) is the lower part of the Brain, adjoining and structurally continuous with the Spinal cord. It is rostral to the medulla oblongata, caudal to the midbrain, and ventral to the cerebellum. The medulla oblongata is the lower portion of the Brainstem. It deals with autonomic functions such as breathing and blood pressure In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species In biological anatomy the mesencephalon (or midbrain) comprises the Tectum (or corpora quadrigemini Tegmentum, the ventricular mesocoelia (or "iter" In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species The cerebellum ( Latin: "little brain" is a region of the Brain that plays an important role in the integration of sensory perception In humans and other bipeds this means it is above the medulla, below the midbrain, and anterior to the cerebellum. Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus Bipedalism is a form of Terrestrial locomotion where an organism moves by means of its two rear limbs In fields of Anatomy, anatomical terms of location are descriptive terms to help identify relative positions or directions within a species

Contents 1 Function 2 Anatomy of the pons 3 Cranial nerve nuclei 4 Related diseases 5 Additional images 6 References 7 External links

Function

The pons relays sensory information between the cerebellum and cerebrum; aids in relaying other messages in the brain; controls arousal, and regulates respiration (see respiratory centres). A relay is an electrical Switch that opens and closes under the control of another Electrical circuit. Senses are the physiological methods of Perception. The senses and their operation classification and theory are overlapping topics studied by a variety of fields Information as a concept has a diversity of meanings from everyday usage to technical settings The cerebellum ( Latin: "little brain" is a region of the Brain that plays an important role in the integration of sensory perception The telencephalon (tɛlɛnˈsɛfəlɒn cerebrum, or forebrain is the most Anterior or especially in humans most Dorsal region of the The ventral respiratory group ( VRG) is a column of neurons located in the ventrolateral region of the medulla, extending from the caudal facial nucleus to -400μm In some theories, the pons has a role in dreaming. Dreams are the images sounds thoughts and feelings experienced while Sleeping, particularly strongly associated with Rapid eye movement sleep. ^[1]

Anatomy of the pons

The "knob-like" process (Basal pons) is 2 centimeters long and located on the anterior (front) of the brainstem. It is formed of nerves that travel from one side (left or right) to the other. Most other fibres in the brainstem travel up and down.

The posterior (back) surface of the pons forms part of the wall of the fourth ventricle of the brain. The fourth ventricle is one of the four connected fluid-filled cavities within the human Brain.

Most blood to the pons is supplied by pontine arteries. The pontine arteries are a number of small vessels which come off at right angles from either side of the Basilar artery and supply the Pons and adjacent parts of These are small arteries that branch off the basilar artery (of the Circle of Willis). In Human anatomy, the basilar artery is one of the arteries that supplies the Brain with oxygen-rich blood The circle of Willis (also called the cerebral arterial circle or arterial circle of Willis) is a circle of arteries that supply blood to the Brain Blood also comes from the anterior inferior, and superior cerebellar arteries. The anterior inferior cerebellar artery passes backward to be distributed to the anterior part of the under surface of the Cerebellum, anastomosing with the Posterior inferior The superior cerebellar artery (SCA arises near the termination of the Basilar artery

There are two main domains in the pons for control of respiration:^[2]

• the apneustic center - lower pons
• the pneumotaxic center - upper pons

Cranial nerve nuclei

A number of cranial nerve nuclei are present in the pons:

• mid-pons: The chief or pontine nucleus of the trigeminal nerve sensory nucleus (V)
• mid-pons: the motor nucleus for the trigeminal nerve (V)
• lower down in the pons: abducens nucleus (VI)
• lower down in the pons: facial nerve nucleus (VII)
• lower down in the pons: vestibulocochlear nuclei (vestibular nuclei and cochlear nuclei) (VIII)

Related diseases

• Central pontine myelinosis, a demyelination disease that causes difficulty with swallowing and speaking

Additional images

Scheme showing the connections of the several parts of the brain. Control of ventilation ( control of respiration) refers to the physiological mechanisms involved in the control of physiologic ventilation. The pneumotaxic center, also known as the pontine respiratory group ( PRG) is a network of neurons in the Rostral Dorsal Lateral Cranial nerves are Nerves that emerge directly from the Brain stem in contrast to Spinal nerves which emerge from segments of the Spinal cord. The trigeminal nerve (the fifth Cranial nerve, also called the fifth nerve or simply V) is responsible for sensation in the face The sensory trigeminal nerve nucleus is the largest of the Cranial nerve nuclei and extends through the whole of the Brainstem, Midbrain to medulla The abducens nucleus is the originating nucleus from which the Abducens nerve emerges - a Cranial nerve nucleus. The facial motor nucleus is a collection of Neurons in the Brainstem that belong to the Facial nerve ( Cranial nerve VII The vestibulocochlear nerve (also known as the auditory or acoustic nerve) is the eighth of twelve Cranial nerves, and is responsible for transmitting sound The vestibular nuclei are the Cranial nuclei for the Vestibular nerve. The cochlear nuclei consist of (a the Dorsal cochlear nucleus, corresponding to the Tuberculum acusticum on the dorso-lateral surface of Central pontine myelinolysis or osmotic demyelination syndrome is a demyelinating lesion in the brain that occurs with rapid correction of Hyponatremia A demyelinating disease is any Disease of the Nervous system in which the Myelin sheath of Neurons is damaged	Superficial dissection of brain-stem. Lateral view.	Superficial dissection of brain-stem. Ventral view.	Coronal section of the pons, at its upper part.
Dissection showing the projection fibers of the cerebellum.	Sagittal section through right cerebellar hemisphere. The right olive has also been cut sagitally.	Scheme of roof of fourth ventricle. The arrow is in the foramen of Majendie.	Mesal aspect of a brain sectioned in the median sagittal plane.
Coronal section of brain immediately in front of pons.	Hind- and mid-brains; postero-lateral view.	Median sagittal section of brain.	Dissection showing the course of the cerebrospinal fibers.
Terminal nuclei of the cochlear nerve, with their upper connections.	Terminal nuclei of the vestibular nerve, with their upper connections.	The hypophysis cerebri in position. The pituitary gland, or hypophysis, is an Endocrine gland about the size of a Pea. Shown in sagittal section. A sagittal plane of the human body is an imaginary plane that travels from the top to the bottom of the body dividing it into left and right portions	Pituitary and pineal glands
Axial section of the Brainstem (Pons) at the level of the Facial Colliculus	Human cerebrum lateral view	Human brain frontal (coronal) section	Human brainstem anterior view

References

1. ^ The "Science of Dreaming" in Neurontic: Psychology for the Modern Mind..
2. ^ Physiology at MCG 4/4ch6/s4ch6_10

External links

• Diagram at UCC
• BrainMaps at UCDavis Pons

The Medical College of Georgia, also known as MCG, is a public medical Research university located in downtown Augusta Georgia. BrainMaps is an NIH -funded interactive zoomable high-resolution digital brain atlas and virtual microscope that is based on more than 20 million megapixels (50 terabytes

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