Revision lecture

Question 1

Describe gray matter

Answer 1

• cell bodies, dendrites, unmyelinated axons, axon terminals, neuroglia
• includes cerebral cortex and deep nuclei
• little or no myelin
• gray from Nil bodies

Question 2

Describe white matter

Answer 2

• bundles of myelinated axons (fibre tracts)
• 3 types of tracts: commissural, association, projection
• fatty myelin gives white colour

Question 3

Describe commissural fibres and list the major ones

Answer 3

• connect cortices of R and L hemispheres

1) corpus callossum (largest)
2) anterior and posterior commissures
3) fornix

Question 4

Describe the association fibres and list the major ones

Answer 4

• connect regions of cerebral cortex within ONE hemisphere

1) superior longitudinal fasciculus
2) inferior longitudinal fasciculus
3) cingulum

Question 5

Describe the projection fibres and list the major ones

Answer 5

• connect cortex with lower levels of brain and spinal cord

1) internal capsule

Question 6

Broca’s area vs Wernicke’s area

Answer 6

Broca: expressive speech, production of speech

Wernicke: interpretation of sounds

Question 7

What is the limbic system?

Answer 7

• made of the thalamus and hypothalamus

* emotions and more

Question 8

What is the blood supply of the internal capsule?

Answer 8

Anterior limb:
• anterior cerebral artery

Genu:
• middle cerebral artery

Posterior limb:
• anterior choroidal artery

Question 9

What is the major blood supply of the telencephalon?

Answer 9

Internal carotids supply 80% of it

Question 10

What do the vertebral arteries supply?

Answer 10

• brainstem
• cerebellum
• parts of spinal cord
• parts of diencephalon, occipital and temporal lobes

Question 11

What is the carotid siphon?

Answer 11

• located in the cavernous sinus
• then pierces the dura into the subarachnoid space, giving off:
-ophthalmic
-posterior communicating
-anterior choroidal
-anterior cerebral
-middle cerebral

Question 12

What is the diencephalon?

Answer 12

• surrounded by cerebral hemispheres (telencephalon)
• surrounds 3rd ventricle
• includes: thalamus, hypothalamus, epithalamus, sub thalamus and retina•

Question 13

What is the internal capsule?

Answer 13

• projection fibre tracts between cortex and spinal cord

* contains ascending and descending fibres

Question 14

What tracts are in the anterior limb of the internal capsule?

Answer 14

• corticopontine

* thalamocortical

Question 15

What tracts are in the genu of the internal capsule?

Answer 15

• corticobulbar

Question 16

What tracts are in the posterior limb of the internal capsule?

Answer 16

• corticospinal
• corticonulbar (few)
• thalamocortical

Question 17

What division of the thalamus does motor planning and control and is principal path to somatosensory cortex?

Answer 17

Ventral anterior (VA)

• VA and VL do motor planning
• VPL and VPM are somatosensory

Question 18

What is the role of the hypothalamus?

Answer 18

Homeostasis:
• humoral
• visceromotor
• somatic motor responses to homeostatic stimuli

Question 19

What is the relationship of pituitary gland and hypothalamus?

Answer 19

• hypothalamus release hormones that stimulate anterior pit

* hypothalamus stores hormones in posterior pit

Question 20

What is the blood supply to the cerebellum?

Answer 20

Posterior cerebellum • PICA

Anterior inferior cerebellum • AICA

Superior anterior cerebellum • SCA

Question 21

What is the flow of CSF?

Answer 21

(Lateral ventricle choroid plexus) lateral ventricles

• > inter ventricular foramen
• > 3rd ventricle (+ more from its plexus)
• > cerebral aqueduct
• > 4th ventricle (+ more from its plexus)
• > lateral and median apertures
• > subarachnoid space
• > arachnoid vili
• > venous blood

Question 22

List the medial, and the lateral brainstem tracts

Answer 22

Medial brainstem tracts:
• tectospinal
• vestibulospinal
• reticulospinal

Lateral brainstem tracts:
• rubrospinal