Lec 8: Structure of Brain Stem

What does Brainstem help with

Balance, Posture, and walking

What creates the brainstem

Medulla oblongata mering seamlessly with spinal cord

What does medulla oblongata control?

vital involuntary reflexes such as, swallowing, vomiting, sneezing, coughing, and regulation of cardiovascular and respiratory activity.

What is the medulla the origin of?

7 Cranial Nerves

Located on the ventral surface, the junction between medulla and pons and marked by a prominent sulcus called?

Ponteo Medullary Sulcus

Located on dorsal surface, at the junction between pons and medulla is an imaginary line that passes between the caudal margins of _____ ____ _____

Middle, Cerebellar, and Peduncles

Where does Cranial 4 come from

Dorsal Part of brainstem

In passing rostrally, the central canal shifts progressively from _____ and in the rostral medulla it opens into the _____ _____

Dorsally, fourth ventricele

What goes through Luschka?

CSF

Lateral walls of rostral part of the fourth ventricle are made up of what?

superior and inferior cerebellar peduncles

How are brainstem and cerebellum connected?

Cerebellar Peduncles

Prominent oval swelling located laterally. It contains the rootlets of CN IX, X XI which are attached to the medulla just dorsal to ____

Olive

Where is the pyramidal decussation?

on the ventral side of medulla

Where are Gracile and Cuneate tubercles loated?

Dorsal side at the rostral end of medulla

Pyramid: Eminences on ventral side of medulla and consists of what?

corticospinal fibers

Located just dorsal to rootlets of CN 9, 10, and 11. It marks the portion of the dorsal spinocerebellar tract.

Tuberculum Cinereum

[Cranial Nerves]

Attached to the brain stem at caudal border of pons and lateral to abducens

Abducens

[Cranial Nerves]

Located lateral to facial nerve at caudal border of pons

Vestibulocholear Nerve

[Cranial Nerves]

Attached to the medulla along a line between the lovie and the tuberculum cinereum

Glossopharyngeal, Vagus, Cranial Division of Accessory

[Cranial Nerves]

Emerges along the ventrolateral sulcus between the pyramid and olive

Hypoglossal Nerve

Main Function is to

“ Connect the cerebellum to the rest of the brain and modify the respiratory output of medulla”

Pons

On ventral portion and is a shallow groove that runs along the midline, what is it know as?

Basilar Sulcus

True or False

“ Laterally pons merge into the middle cerebral peduncles”

True

Cranial nerve that is attached between pons and peduncle and has 3 branches Ophthalmic, Maxillary and Mandibular

Trigeminal

What portion of pons contains ascending and descending tracts

Tegmentum (Dorsal Portion)

What forms the floor of pons in the dorsal surface

Fourth Ventricle

Basis Pedunculi have what on either side of white matter

Corticospinal, Corticobulbar, and corticopontine fibers

[Cranial Nerves]

Emerges from the side of interpeduncular fossa

Oculomotor Nerve

What primary forms the cerebral Peduncle

The lateral surface of midbrain

Only Nerve coming from dorsal aspect of mid brain?

Trochlear Nerve

Superior Colliculi is for what?

Ocular Movement

Inferior Colliculi is for what?

Hearing

How is brainstem divided longitudinally

Anterior and posterior

What type of tracts travel thorough brainstem

Sensory, autonomic, and motor vertical

How do sensory tracts carry information?

From spinal cord to the brain

How do motor tracts convey information from cortex

From cortex to brainstem and spinal cord