lecture 4 - neuroanatomy 3-4 Flashcards
Where does CNI arise?
The cribriform plate
What is the name for the structure where the left and right optic nerves coming together?
Optic chiasm
What structure carries fibres from optic chiasm to the occipital lobe?
Optic tract
What is the function of CNI (olfactory nerve)?
Special sense of smell
What is the function of CNII (optic nerve)?
Special sense of vision
What is the function of CNIII (oculomotor nerve)?
motor supply to some extraocular muscles and all of the intrinsic smooth muscles of the eye
What is the function of CNIV (trochlear nerve)?
motor supply to the superior oblique muscle at the back of the eye
What is the function of CNV (trigeminal nerve)?
somatic sensation of face and anterior tongue, motor to muscles of mastication
What is the function of CNVI (abducens nerve)?
motor to lateral rectus muscle, which abducts the eye
What is the function of CNVII (facial nerve)?
motor to muscles of facial expression, taste on anterior tongue
What is the function of CNVIII (vestibulocochlear nerve)?
special senses of hearing and balance
What is the function of CNIX (glossopharyngeal)?
major nerve for taste, sensation of posterior tongue and pharynx
What is the function of CNX (vagus nerve)?
motor/sensory of viscera of thorax & abdomen, motor to pharynx & larynx muscles
What is the function of CNXI (accessory nerve)?
motor to sternomastoid and trapezius muscles
What is the function of CNXII (hypoglossal nerve)?
motor to all tongue muscles
Which cranial nerves are associated with the forebrain?
CNI, CNII
Which cranial nerves are associated with the brain stem?
CNIII-CNXII
What structures anchor the cerebrum to the midbrain?
Cerebral peduncles
What side of the midbrain are the cerebral peduncles on?
The ventral/anterior side
What are the 4 components of the corpora quadrigemia?
Superior colliculli (2), inferior colliculli (2)
Which cranial nerves are associated with the midbrain?
Oculomotor (III), Trochlear (IV)
What level of the brain stem has the substantia nigra?
Midbrain
What level of the brain stem has the red nucleus?
Midbrain
What is the main function of the superior colliculli?
Visual processing - detect moving objects, coordinate head and eye movements
What is the main function of the inferior colliculli?
Auditory processing - startle reflex
What structure lies immeidately deep to the cerebral peduncles?
Substantia nigra
What gives the substantia nigra its black colour?
melanin pigment, which is a precursor to dopamine
What part of the brain is the substantia nigra ‘functionally linked’ to?
The basal nuclei
What is the disease associated with dopamine neuron degeneration in the substantia nigra?
Parkinson’s disease
What gives the red nucleus its colour?
Iron pigment
What ventricle does the pons form a wall of?
The 4th ventricle
Which cranial nerves are associated with the pons?
CNV, CNVI, CNVII, CNVIII
Where do the cotricospinal tracts run in the medulla?
Through the pyramid on the ventral part
What is the function of the medullary pyramids?
Contain motor fibres of the corticospinal tracts
At what level is the pyramidal decussation?
The level of the foramen magnum
What cranial nerves are associated with the medulla?
CNIX, CNX, CNXI, CNXII
Where in the brainstem are the cardiovascular centres found?
The medulla
Where in the brain stem are the respiratory centres found?
Pons and medulla
How is the cerebellum connected to the brain stem?
Cerebellar peduncles
Which dural fold connected to the posterior cerebellar incisure?
falx cerebelli
What part of the cerebellum sits between the left and right cerebellar hemispheres?
Vermis
What is the name for the ‘leaves’ of the cerebullum?
Folia
What is the arbor vitae of the cerebullum?
The white matter found deep within the cerebellum
What is the function of the superior and inferior medullary velum?
They sit between the cerebellar peduncles and form the roof of the fourth ventricle
Which of the medullary velum has choroid plexuses and therefore produces CSF?
Inferior medullary velum
What are the 3 key functional divisions of the cerebellum?
Spinocerebellum, cerebrocerebellum, vestibulocerebellum
What parts of the cerebellum make up the spinocerebellum?
Vermis, intermediate hemipsheres
What parts of the cerebellum make up the cerebrocerebellum?
Lateral hemispheres
What parts of the cerebellum make up the vestibulocerebellum?
Flocculonodular node - the nodulus and 2 flocculus
What is the function of the spinocerebellum?
Posture and movement of the trunk and limbs
What is the function of the cerebrocerebellum?
Planning movement
What is the function of the vestibulocerebellum?
Balance, head & eye movements
What does the superior cerebellar peduncle connect?
The cerebellum to the midbrain
What does the middle cerebellar peduncle connect?
The cerebellum to the pons
What does the inferior cerebellar peduncle connect?
The cerebellum to medulla
What are the 3 key deep nuclei of the cerebellum?
Dentate nuclei, interposed nuclei, fastigial nuclei
How does the cerebellum receive information about intended movements?
From the motor cortex, via the pons and into the cerebellum via the middle cerebellar peduncle
How does the cerebellum receive information about actual movements?
From peripheral sense organs via the medulla into the cerebellum via the inferior cerebellar peduncles
How does the cerebellum compare actual and intended movements?
Takes inputs from middle and inferior cerebellar peduncles and compares in the deep nuclei
How does information about correction of movements leave the cerebellum?
Via the superior and inferior cerebellar peduncles
What are some of the common signs/symptoms of cerebellar dysfunction?
ataxia, tremor, nystagmus, headache, vomiting
