W1:S1 - External Features of the Brainstem and Diencephalon Flashcards
What are the 3 parts of the brainstem?
Midbrain
Pons
Medulla
Which cranial cavity does the brainstem lie in?
Posterior
Which two embryological vesicles give rise to the brainstem?
Mesencephalon
Rhomboencephalon
What parts of the ventricular system lie inside the brainstem?
Cerebral aqueduct
4th ventricle
What nerves emerge from the pontomedullary junction?
Abducens
Facial
Vestibulocochlear
Which pontomedullary nerve has the longest course?
Abducens
What condition does the long course of this nerve make it susceptible to?
Raised ICP
What is the consequence of abducens being injured?
Double vision when trying to focus on something in the midline OR if bilateral an inability to look midline (medial rectus paralysed)
What are the pyramids formed by?
Motor fibres of the corticospinal tracts
What is the function of the superior olivary body?
An important component of the auditory pathways
What is the function of the inferior olivary bodies?
Coordinate signals from spinal cord to cerebellum about proprioreception
What structure does the open part of the medulla open into?
4th ventricle
What cranial nerve leaves the pons?
Trigeminal
What fibres are the cerebellar peduncles made of?
Centripetal fibres (incoming fibres)
What part of the brain lies immediately superior to the midbrain?
Thalamus
What is the function of the superior colliculus?
Recieves visual stimulus from the retina and reacts with head and eye movements to environmental stimuli
- Like how your eyes follow the ball during a conversion
What is the function of the inferior colliculi
Processing auditory stimuli
What is the diencephalon made up of?
Structures either side of the 3rd ventricle
- The thalamus
- Hypothalamus
- Epithalamus
- Subthalamus
Which two parts of the brain does the diencephalon lie in between?
Cerebrum
Midbrain
What is shown here?
Mamillary bodies
