Mid Sem Miscellaneous (W1-5)

Question 1

1. Name the arteries of the Circle of Willis and those associated (16 studied)

Answer 1

(From roughly top to bottom on a standard schematic:)

Anterior Communicating
Anterior Cerebral
Middle Cerebral Internal
Carotid Opthalmic
Anterior Choroidal
Posterior Communicating
Perforating
Posterior Cerebral
Superior Cerebellar
Basilar
Pontine
Anterior Inferior Cerebellar
Vertebral
Posterior Inferior Cerebellar
Anterior Spinal

Question 2

2. Function: Pons?

Answer 2

Relay centre for info passing from cerebral cortex to cerebellum.

Contains nuclei of CN V, VI, VII, respiratory control centres, and long motor & sensory tracts.

Question 3

3. Function: Medulla?

Answer 3

Regulating many autonomic functions (e.g. BP, HR, Respiratory rate, coughing, vomiting reflexes). Contains nuclei of CN VII-XII

Question 4

4. Function: Corpus Callosum?

Answer 4

The largest of the cerebral commissures, allows info transmission bw cerebral hemispheres, enabling memory traces to be stored bilaterally.

Question 5

5. Function: Cerebral Peduncle?

Answer 5

Involved in somatosensory perception, motor & autonomic control.

Question 6

6. Function: Cingulate gyrus?

Answer 6

Part of the limbic area of the cerebral cortex - emotion formation & processing, learning, memory.

Functions in the control of innate behaviours (ie. those related to the survival of the species).

Inputs: thalamus, neocortex

Projections: entorhinal cortex via cingulum

Question 7

7. Function: 4th Ventricle?

Answer 7

As part of the ventricular system the fourth ventricular system produces CSF.

It’s also the site from which CSF escapes from the ventricular system into the Suabarachnoid Space.

Question 8

8. Function: Lingual Gyrus?

Answer 8

Forms the lower bank of the Calcarine Sulcus, which is the part of the primary visual area which processes info concerning the superior part of the visual field.

Question 9

9. Function: Confluence of Sinuses?

Answer 9

The confluence of the sinuses is the site where the superior sagittal and straight sinuses unite with the transverse sinuses.

Question 10

10. Function: Cerebral Aqueduct?

Answer 10

The cerebral aqueduct is a canal which connects the third and fourth ventricles.

Question 11

11. Function: Inferior Colliculi?

Answer 11

Auditory Relay nuclei

Question 12

12. Function: Superior Colliculi?

Answer 12

Visual Reflexes

Question 13

13. Function: Tectum?

Answer 13

The tectum (roof) of the midbrain is formed by the superior colliculi (involved in visual reflexes) and inferior colliculi (auditory relay nuclei).

Question 14

14. Function: Thalamus?

Answer 14

Important relay & integration centre for both motor & sensory info en route to the cerebral cortex.

Also involved in regulating overall activity levels in the cortex.

Question 15

15. Function: Lateral Ventricle?

Answer 15

Produces and contains CSF.

Question 16

16. Function: Interventricular Foramen?

Answer 16

(aka Foramen of Monro) Allows CSF to circulate from the Lateral Ventricle into the 3rd Ventricle

Question 17

17. Function: Hypothalamus?

Answer 17

Involved in maintenance of homeostasis, regulation of feeding, drinking & sexual activity, circadian rhythms and emotional expression.

Question 18

18. Function: Optic Chiasm?

Answer 18

Formed by the partial decussation of the optic nerve fibres, ensuring that the visual fields of both eyes are represented bilaterally in the visual cortex.

Question 19

19. Function: Straight Sinus?

Answer 19

Formed by union of great cerebral v. and inf. sagittal sinus, drains blood from the deep structures of the brain to the confluence of the sinuses.

Question 20

20. Function: Parietal Lobe?

Answer 20

Involved in the recognition of somatosensory stimuli and in the integration of visual, somatosensory & auditory info.

Question 21

21. Function: Marginal Sulcus?

Answer 21

Forms the posterior boundary of the Paracentral Lobule.

Question 22

22. Function: Paracentral Lobule?

Answer 22

Includes the primary motor & somatosensory areas for the leg & foot.

Question 23

23. Function: Anterior Commissure?

Answer 23

Contains fibres which link the cortex of the temporal lobe of one side with the corresponding area on the opposite side, as well as fibres linking the olfactory tract of one side with the olfactory tract & bulb of the opposite side.

Question 24

24. Function: Brainstem?

Answer 24

Involved in regulation of autonomic activity, consciousness and the maintenance of equilibrium.

Also contains ascending & descending tracts as well as cranial nerve nuclei.

Question 25

25. Function: Frontal Lobe

Answer 25

Controls voluntary movements of the opposite side of the body (primary & premotor areas) and is important in the determination of mood, emotional responses, motivation and anxiety levels (prefrontal area).

Question 26

26. Function: Hypophysis?

Answer 26

(aka Pituitary Gland) Produces a number of hormones including TSH, GH, ACTH, FSH, LH and Prolactin.

Question 27

27. Function: Mammillary Bodies?

Answer 27

Component of the limbic system and is known to play a role in the formation of memory.

Question 28

28. Function: Superior Cistern

Answer 28

(aka Quadrigeminal Cistern) Part of the Subarachnoid Space, between the splenium of the corpus callosum and the midbrain.

It is traversed by the great cerebral vein.