Topography of the Brain

Question 1

What is white matter?

Answer 1

Myelinated axons

Question 2

What is grey matter?

Answer 2

Neuronal cell bodies

Question 3

What is a tract?

Answer 3

Fibre pathway passing through the CNS carrying a specific modality

Question 4

Where does the 2 internal carotid arteries enter the skull to supply the brain?

Answer 4

Carotid canal

foramen lacerum

Question 5

Where does the 2 vertebral arteries enter the skull to supply the brain?

Answer 5

Foramen magnum

Question 6

What is the Circle of Willis?

Answer 6

Branches of the internal carotid artery join together from both sides and with the posterior cerebral artery to form a continuous circle at the base of the brain

Question 7

What is the importance of the Circle of Willis?

Answer 7

Protective feature against vaso-occlusion of large arteries

Question 8

What branches does the internal carotid artery give?

Answer 8

Anterior cerebral artery
Middle cerebral artery
Posterior communicating arteries

Question 9

What artery is formed by the joining of the 2 vertebral arteries on the ventral surface of the brainstem?

Answer 9

Basilar artery

Question 10

What does the vertebro-basilar system supply?

Answer 10

Gives branches that supply the brainstem and cerebellum

Question 11

Where does the basilar artery end?

Answer 11

Level of the midbrain - divides into 2 posterior cerebral arteries

Question 12

What do the posterior cerebral arteries supply?

Answer 12

Posterior part of the cerebral hemispheres

Question 13

What does the anterior cerebral artery supply?

Answer 13

Medial aspect of cerebral hemispheres excluding occipital lobe

Question 14

What does the middle cerebral artery supply?

Answer 14

Lateral aspect of cerebral hemispheres

Question 15

What does the posterior cerebral artery supply?

Answer 15

Inferior aspect of cerebral hemispheres and occipital lobe

Question 16

Where do superficial and deep veins of the brain drain into?

Answer 16

Venous sinuses which lie between 2 layers of dura mater

Question 17

Where do the dural venous sinuses drain into?

Answer 17

Internal jugular veins

Question 18

When does the neural tube divide into 3 primary vesicles?

Answer 18

As soon as it is formed

Week 4

Question 19

When does the neural tube divide into secondary vesicles?

Answer 19

Week 5

Question 20

What is in the brainstem?

Answer 20

Midbrain, pons, medulla

Question 21

What are the functions of the brainstem?

Answer 21

Pathway for fibre tracts between higher and lower centres
Nucleii involved with 10/12 cranial nerves
Brainstem centres produce the rigidly programmed automatic behaviours that are essential for survival

Question 22

What is the cavity in the medulla called?

Answer 22

IV ventricle

Question 23

What does the medulla become?

Answer 23

Continues as spinal cord and foramen magnum of cranium

Question 24

What are the surface features of the medulla?

Answer 24

Pyramids and their decussation
Olives laterally
Connected to cerebellum by inferior cerebellar peduncle
CN IX, X, XI, XII from its surface

Question 25

Where is the IV ventricle in relations to the pons?

Answer 25

Posterior

Question 26

What are the surface features of the pons?

Answer 26

Middle cerebellar peduncle | CN V, VI, VII, VIII originate from its surface

Question 27

What does the midbrain develop from?

Answer 27

Mesencephalon

Question 28

What is the central cavity in the midbrain called?

Answer 28

Cerebral aqueduct

Question 29

What are the surface features of the midbrain?

Answer 29

Cerebral peduncle Superior cerebellar peduncle Corpora quadrigemina (superior and inferior collicolus) Origin of oculomotor and trochlear nerves

Question 30

What cranial nerve is the only nerve to originate posteriorly?

Answer 30

Trochlear (IV)

Question 31

What connects the 3rd and 4th ventricles in the brainstem?

Answer 31

Cerebral aqueduct

Question 32

What separates the right and left cerebellar hemispheres?

Answer 32

Vermis

Question 33

What are the 3 lobes of each cerebellar hemisphere?

Answer 33

Anterior Posterior Flocculonodular

Question 34

What does the surface of the cerebellum consist of?

Answer 34

Sulci | Folia

Question 35

How many cerebellar peduncles connect the cerebellum to the brainstem?

Answer 35

3

Question 36

What are the 2 main functions of the cerebellum?

Answer 36

Posture maintenance | Fine tuning motor activity

Question 37

What tests identify ataxia?

Answer 37

Finger - nose test Knee - heel test Walking in a straight line

Question 38

Where is the diencephalon?

Answer 38

Deep within cerebral hemispheres, around the III ventricle

Question 39

Which vesicle does the diencephalon develop from?

Answer 39

Diencephalic vesicle (part of forebrain vesicle)

Question 40

What are the paired structures within the diencephalon?

Answer 40

Thalamus Hypothalamus (+ pituitary) Epithalamus (pineal gland)

Question 41

What is the thalamus?

Answer 41

Egg shaped body on either side of the III ventricle | Makes up 80% of the diencephalon

Question 42

What groups of nucleii lie within the thalamus?

Answer 42

Anterior Medial Lateral

Question 43

What is the lateral group of nucleii in the thalamus involved in?

Answer 43

Processing sensory information

Question 44

What is the function of the thalamus?

Answer 44

Sensory relay station

Question 45

Where is the hypothalamus?

Answer 45

Below the thalamus separated from it by the hypothalamic sulcus

Question 46

What is the hypothalamus' function?

Answer 46

Main visceral control centre | Essential for overall homeostasis

Question 47

What is the homeostatic role of the hypothalamus?

Answer 47

``` Autonomic control centre Body temperature regulation Regulation of food intake Regulation of water balance and thirst Regulation of sleep-wake cycle Control of endocrine system functioning ```