Control Lecture 5: Visual pathways

Question 1

What are the general layers of the retina, in order from the choroid to the vitreous humour in the posterior compartment where light arrives?

Answer 1

Pigmented epithelium
Photoreceptors
Primary neurons
Secondary neurons

Question 2

What are the primary neurons in the visual pathway?

Answer 2

Bipolar cells

Question 3

What are the secondary neurons in the visual pathway?

Answer 3

Ganglion cells

Question 4

What other neurological cells are present in the retina apart from bipolar and ganglion cells, and what is their function?

Answer 4

Interneurons

Modulate and adapt the system

Question 5

Where do ganglion cells converge?

Answer 5

Optic disc

Question 6

Why are the photoreceptors deep to the neurological cells within the retina, further from the arriving light?

Answer 6

Reduces the intensity of light hitting the photoreceptors

Question 7

Are bipolar and ganglion cells counted as being in the CNS or PNS/

Answer 7

CNS

Question 8

Which lobe of the brain do the tertiary neurons of the visual pathway project to?

Answer 8

Occipital

Question 9

Which sulcus is the primary visual cortex centred around?

Answer 9

Calcarine

Question 10

Which nucleus in the thalamus does the visual pathway pass through?

Answer 10

Lateral geniculate nucleus

Question 11

Where does the optic nerve pass out of the skull?

Answer 11

Optic canal

Question 12

Which meningeal layer forms the sclera of the eyeball?

Answer 12

Dura mater

Question 13

Which meningeal space persists in the eyeball?

Answer 13

Subarachnoid

Question 14

What does CSF buildup cause in the eyes?

Answer 14

Papilloedema

Question 15

Where do the blood vessels of the eye radiate from?

Answer 15

Optic disc

Question 16

Which side of the left eye detects light from the left hand side?

Answer 16

Nasal

Question 17

Which side of the right eye detects light from the left hand side?

Answer 17

Temporal

Question 18

Which side of the right eye will be associated with fibres in the same optic tract as fibres from the temporal side of the left eye?

Answer 18

Nasal

Question 19

Do fibres from the nasal or the temporal side of the eye run in the contralateral optic tract?

Answer 19

Nasal

Question 20

Do fibres from the nasal or the temporal side of the eye run in the ipsilateral optic tract?

Answer 20

Temporal

Question 21

What do fibres travel in between the thalamus and the cerebral cortex in the visual pathway?

Answer 21

Optic radiations

Question 22

Do fibres running in the superior trajectory to the cortext originate from the upper or lower eye?

Answer 22

Lower

Question 23

Can the calcarine sulcus be seen in a medial or a lateral view of the brain?

Answer 23

Medial

Question 24

What kind of fibres pass between the striate cortex and the visual association cortex?

Answer 24

Association

Question 25

What is the cortex around the calcarine sulcus (primary visual cortex) called?

Answer 25

Striate cortex

Question 26

Does information from the upper or the lower visual field end up at the upper bank of the calcarine sulcus?

Answer 26

Lower

Question 27

Where does information from the macula end up in the cortex?

Answer 27

Occipital pole

Question 28

What is the name for a localised patch of blindness?

Answer 28

Scotomia

Question 29

What is the name for loss of half of the visual field?

Answer 29

Hemianopia

Question 30

What is the name for loss of a quarter of the visual field?

Answer 30

Quadrantanopia

Question 31

What is it called when visual field loss is the same on both sides?

Answer 31

Homonymous

Question 32

What is it called when visual field loss is different on both sides?

Answer 32

Heteronymous

Question 33

Monocular blindness. Where is the lesion?

Answer 33

Unilateral optic nerve

Question 34

Heteronymous hemianopia. Where is the lesion?

Answer 34

Middle of the optic chiasma | Lesion takes out both contralateral fibres from nasal sides

Question 35

Homonymous hemianopia. Where is the lesion?

Answer 35

Unilateral optic tract

Question 36

Homonymous quadrantanopia. Where is the lesion?

Answer 36

Single trajectory of the optic radiations eg. inferior trajectory on left side -> upper right quadrant field loss

Question 37

Homonymous hemianopia with macula sparing. Where is the lesion?

Answer 37

Superior and inferior trajectories on one side

Question 38

Bilateral central scolomas. Where is the lesion?

Answer 38

Occipital pole