Pons Flashcards
What does the word Pons mean?
Bridge
Where is the pons located?
The pons lies directly superior to the medulla and anterior to the cerebellum and is about 2.5 cm (1 in.) long
What types of structures make up the pons?
The pons consists of both nuclei and tracts.
What are the connections made by in the pons and what do they do?
These connections are provided by bundles of axons. Some axons of the pons connect the right and left sides of the cerebellum. Others are part of ascending sensory tracts and descending motor tracts.
What are the two major structural components of the pons?
The pons has two major structural components: a ventral region and a dorsal region.
What does the ventral region of the pons form and what does it do?
The ventral region of the pons forms a large synaptic relay station consisting of scattered gray centers called the pontine nuclei. Entering and exiting these nuclei are numerous white matter tracts, each of which provides a connection between the cortex (outer layer) of a cerebral hemisphere and that of the opposite hemisphere of the cerebellum. This complex circuitry plays an essential role in coordinating and maximizing the efficiency of voluntary motor output throughout the body.
What is the dorsal region of the pons?
Contains?
The dorsal region of the pons is more like the other regions of the brain stem, the medulla and midbrain. It contains ascending and descending tracts along with the nuclei of cranial nerves.
What other nuclei are located in the pons?
Than the dorsal and ventral.
Other nuclei located in the pons are the pneumotaxic area and the apneustic area. Together with the medullary rhythmicity area, the pneumotaxic and apneustic areas help control breathing.
The pons also contains nuclei associated with the following four pairs of cranial nerves:
Trigeminal (V) nerves
Abducens (VI) nerves
Facial (VII) nerves
Vestibulocochlear (VIII) nerves
The pons contains nuclei associated with 4 of the cranial nerves, what are they?
Trigeminal (V) nerves
Abducens (VI) nerves
Facial (VII) nerves
Vestibulocochlear (VIII) nerves
Explain the trigeminal nerve in relation to the pons?
Trigeminal (V) nerves. Nuclei in the pons receive sensory impulses for somatic sensations from the head and face and provide motor impulses that govern chewing via the trigeminal nerves.
Explain the abducens nerve in relation to the pons?
Abducens (VI) nerves. Nuclei in the pons provide motor impulses that control eyeball movement via the abducens nerves.
Explain the facial nerves in relation to the pons?
Facial (VII) nerves. Nuclei in the pons receive sensory impulses for taste and provide motor impulses to regulate secretion of saliva and tears and contraction of muscles of facial expression via the facial nerves.
Explain the vestibulocochlear nerves in relation to the pons?
Vestibulocochlear (VIII) nerves. Nuclei in the pons receive sensory impulses from and provide motor impulses to the vestibular apparatus via the vestibulocochlear nerves. These nerves convey impulses related to balance and equilibrium.