6) Forebrain and ventricles

Question 1

What is the forebrain made up of?

Answer 1

Diencephalon and cerebral hemispheres

Question 2

What is the embryological origin of the forebrain?

Answer 2

Prosecephalon

Question 3

What is the forebrain responsible for?

Answer 3

Higher level processing

-perception/interpretation/storage

Question 4

What separates the thalamus from the hypothalamus?

Answer 4

Interthalamic sulcus

Question 5

Where does the 3rd ventricle lie?

Answer 5

Between the 2 thalami

Question 6

Embrologically, the thalamus and hypothalamus appears as 2 swellings of the lateral aspect of the central canal, which lies dorsally and which ventrally?

Answer 6

Thalamus = dorsal 
Hypothalamus = ventral

Question 7

What is the thalamus?

Answer 7

Collection of nuclei

Question 8

What do the nuclei of the thalamus do?

Answer 8

Send fibres to cerebral cortex

- those to defined cortical area = relay nuclei

Question 9

What is the hypothalamus made of?

Answer 9

Several nuclei

Question 10

What is the role of the hypothalamus?

Answer 10

Control of ANS & neuroendocrine function

Question 11

Other than the thalamus and the hypothalamus, what other structures make up the diencephalon?

Answer 11

Subthalamus

Epithalamus

Question 12

Where is the subthalamus found and what is its function

Answer 12

Under thalamus

-involved in motor control

Question 13

What can damage to the subthalamus result in?

Answer 13

Random motor contractions

Question 14

What is the role of the epithalamus and where is it?

Answer 14

Control of circadian rhythm and secretes melatonin

-post to hypothalamic sulcus (includes pineal gland)

Question 15

What are the 3 parts of the corpus callosum?

Answer 15

Splenium - posterior
Body - middle
Genu - anterior

Question 16

What is the septum pellucidum?

Answer 16

Inferior to corpus callosum - thin membrane covering med wall of 3 ventricle

Question 17

What is the fornix?

Answer 17

Bundle of white matter inf to septum pellucidum

Question 18

What is the function of the fornix?

Answer 18

Relay information between the temporal lobe and the hypothalamus
- leads to autonomic controlled processes related to previous experiences (eg sweating at interview)

Question 19

What is the anterior commissure?

Answer 19

Bundle of white matter, ant to fornix

Question 20

What is the function of the anterior commissure?

Answer 20

Helps connect 2 cerebral hemispheres

Question 21

The fornix, corpus callosum and septum pellucidum are all part of what?

Answer 21

Cerebral hemispheres

Question 22

Where does the optic nerve lie in relation to the hypothalamus?

Answer 22

Projects from inf/ant aspect

Question 23

Where do the mamillary bodies lie in relation to the hypothalamus?

Answer 23

Inf/post aspect

Question 24

Where does the pituitary stalk (infundibulum) lie in relation to the hypothalamus?

Answer 24

Projects from inf border, between optic nerve and mamillary bodies

Question 25

What is the interthalamic adhesion?

Answer 25

Contact point of 2 thalami - bisects 3rd ventricle

Question 26

What are the 2 swellings of the telencephalon either side of the midline connected by?

Answer 26

Lamina terminalis

Question 27

What does the embryological lamina terminalis form?

Answer 27

Anterior commissure and corpus callosum

Question 28

What are the 3 horns of the lateral ventricles and which lobe does each occupy?

Answer 28

Anterior horn - frontal lobe Posterior horn - occipital lobe Inferior horn - temporal lobe

Question 29

How thick is the cerebral cortex?

Answer 29

Varies (2-4mm)

Question 30

What is the difference between a short association fibre, a long association fibre and commisural fibre?

Answer 30

Short association fibres - connect 2 adjacent gyri in same hemisphere Long association fibres - connect 2 non-adjecent gyri in same hemisphere Commisural fibres - connect 2 gyri in different hemispheres

Question 31

Corpus callosum and anterior commissure contain what kind of fibres?

Answer 31

Commissural fibres

Question 32

What are the 3 types of fibres found within the brain?

Answer 32

- Association fibres - Commissural fibres - Projection fibres

Question 33

What is the function of projection fibres?

Answer 33

Carry information to/from hemispheres

Question 34

The internal capsule contains what kind of fibres?

Answer 34

Projection fibres

Question 35

What does the deep grey matter of the cerebral hemispheres form

Answer 35

Basal ganglia - group of nuclei

Question 36

What 2 nuclei are found in the basal nuclei?

Answer 36

Caudate nucleus | Lentiform nucleus

Question 37

What 2 parts make up the lentiform nucleus, which lies deeper

Answer 37

``` Globus pallidus Putamen globus (deeper) ```

Question 38

In a horizontal section of the brain which 2 parts of the caudate nucleus can be seen, what shape is it?

Answer 38

Head and tail of caudate nucelus | -C shaped

Question 39

What surrounds the basal ganglia?

Answer 39

White matter

Question 40

What is the function of the basal ganglia?

Answer 40

Involved in movement

Question 41

What is the ventricular system derived from?

Answer 41

Lumen of the neural tube

Question 42

Where are the lateral ventricles?

Answer 42

Within cerebral hemipsheres

Question 43

Where is the 4 th ventricle?

Answer 43

Between cerebellum, pons and medulla

Question 44

What connects the 2 lateral ventricles and 3rd ventricle?

Answer 44

Interventricular foramen

Question 45

How are the 3rd ventricle and 4th ventricle connected?

Answer 45

By cerebral aqueduct

Question 46

How does the CSF produced in the ventricular system pass into the subarachnoid space?

Answer 46

Via 2 lateral and 1 medial apertures of 4th ventricle

Question 47

What structure passes through the 3rd ventricle?

Answer 47

Interthalamic adhesion | - NB no fibres pass through it

Question 48

What is the total volume of CSF in an adult? How much is produced daily?

Answer 48

Total volume ~150 ml ~500ml produced daily

Question 49

In which ventricle is the majority of CSF produced?

Answer 49

Lateral ventricles

Question 50

How is CSF recycled?

Answer 50

Arachnoid granulations pass from subarachnoid space into dural sinuses