THRC.3 Flashcards
What is contained in the rhomboencephalon?
- Myelencephalon
- Medulla oblongata
- Metencephalon
- Pons
- Cerebellum
- Medullary vela
- Rhomboid fossa
Myelencephalon composition
- Medulla oblongata
- Fourth ventricle of the brain
- Caudal medullary velum

Medulla oblongata

Metencephalon

Myelencephalon
Give the arrangement of nuclei in medulla oblongata
- Sensory nuclei are more lateral
- Motor nuclei are more medial
- Parasympathetic nucle between sensory and motor nuclei
Where is medulla oblongata located?
- In fossa medullae oblongata
- Dorsal to basiocciput
The ventral surface of medulla oblongata is divided by…
Ventral median fissure
(continuous from the spinal cord)

Medulla oblongata
Fibres cross the midline to form the…
Pyramidal decussation

Pyramids of vermis
What is represented by the blue crosses?

Decussatio pyramidium
- At the spinomedullary junction*
- Accounts for movements on one side of the body are controlled by the opposite side of the brain*

Pyramids of vermis

Trapezoid body
Belongs to the pons

Ventral median fissure

Decussatio pyramidium
- At the* spinomedullary junction
- Accounts for movements on one side of the body are controlled by the opposite side of the brain*

CN-VI Abducent nerve

CN-VII Facial nerve

CN-VIII Vestibulocochlear nerve

CN-IX Glossopharyngeal nerve

CN-X Vagus nerve

CN-XI Accessory nerve
Recieves additional spinal root from the spinal cord

CN-XII Hypoglossal nerve
13

Location of Olivary nucleus
Function of the olivary nucleus
Control of body motor function
Function of the medulla oblongata
Respiration and circulation control
Composition of the metecephalon
- Pons
- Cerebellum
- Medullary vela
- Rhomboid fossa

Pons

Cerebellum
The dorsal part of the pons
Tegmentum of the pons

CN-V Trigeminal nerve
Location of the motor nucleus of CN-V
Inside the pons
Location of the cerebellum
Dorsal to the fourth ventricle
Structure of the cerebellum
Fissures > Lobes > Small lobules > Folia
Forms the ‘tree of life’
The grey matter of the cerebellum
Cortex cerebelli
White matter of the cerebellum
Medulla
Grey matter in the medulla forms…
Basal nuclei
What attaches the cerebellum to the brainstem?
6 peduncles: 3 on each side
- Rostral cerebellar peduncle
- Caudal cerebellar peduncle
- Middle cerebellar peduncle
Insertion of the rostral cerebellar peduncle
Rostral medullary velum
Insertion of the caudal cerebellar peduncle
- Caudal medullary velum
- Medulla oblongata
Insertion of the middle cerebellar peduncle
Pons
Function of the cerebellum
- Balance
- Co-ordination of skeletal muscles

Rostral medullary velum
Location of the medullary velae
Between the:
- Rhomboid fossa (floor)
- Cerebellum
Structure of the medullary velae
- Tent shape forms
- For the roof over the fourth ventricle
Give the sulcuses of the fossa rhomboidea
What is between them
- Sulcus medianus
- Sulcus limitans x 2
Eminentia medialis is found between them
The walls of the rhomboid fossa are marked by…
Area vestibularis/acustica
(Bilateral eminence)
Obex
The caudal end of the sulcus medianus in fossa rhomboideus
Which cranial nerve nuclei are found in eminentia medialis?
- IX
- X
- XII