The General control of Vision

Question 1

What does the optic nerve tract contain?

Answer 1

nerve fibers from both retinae

Question 2

Where is the optic tract have visual pathways?

Answer 2

in each cerebral hemisphere so it can receive signals from both eyes.

Question 3

Nerve fibers from both retinae are project where?

Answer 3

structures in both right and left visual pathways.

Question 4

How does the visual pathways receive signals?

Answer 4

from only one half of the visual field of each eye.

Question 5

The visual pathway of the left cerebral hemisphere receive signals from where?

Answer 5

the right nasal visual field and vice versa.

Question 6

What forms an optic nerve?

Answer 6

the axons of retinal ganglion cells.

Question 7

What does decussate mean?

Answer 7

cross over

Question 8

The optic nerve fibers from each nasal halves of each retina do what?

Answer 8

cross over at the optic chiasm.

Question 9

The optic nerve fibers from the temporal halves do what?

Answer 9

remain on the same side or ipsilateral.

Question 10

What is ipsilateral?

Answer 10

on the same side.

Question 11

The nerve fibers from nasal halves combine with fibers from opposite temporal halves of the retinae to form what?

Answer 11

the two optic tracts.

Question 12

What forms the two optic tracts?

Answer 12

The nerve fibers from nasal halves combine with fibers from opposite temporal halves of the retinae.

Question 13

Thalamus will transport the signal to where?

Answer 13

the visual cortex

Question 14

What part of the brain does melanopsin perceive light?

Answer 14

mid brain

Question 15

What occurs in the occipital lobe?

Answer 15

Where our vision is processed

Question 16

What is the main role of the superior colliculus?

Answer 16

To react moves eyes without moving head when sounds occur.

Question 17

What is known as the optic tectum?

Answer 17

The superior colliculus.

Question 18

Where is the superior colliculus located?

Answer 18

In the dorsal aspect of the midbrain (mesencephalon).

Question 19

Where is the midbrain located?

Answer 19

in the central to the two thalami.

Question 20

Where is the inferior colliculus located?

Answer 20

located posterior to the superior colliculus.

Question 21

What forms the corpora quadrigemina or tectum?

Answer 21

The inferior an posterior colliculi

Question 22

What does quadrigemina or tectum form?

Answer 22

The dorsal roof of the midbrain.

Question 23

What causes movements of the eye towards a specific direction?

Answer 23

Unconscious signals transmitted from the retina directly to the superior colliculus.

Question 24

The superior colliculus neurons innervate the extra ocular muscles of the eye balls that are:

Answer 24

oculomotor, trochlear, and abducent nerves.

Question 25

What does the inferior colliculus acts as?

Answer 25

a relay site for neurons in the auditory pathway.

Question 26

what serves as the relay nuclei?

Answer 26

the lateral geniculate nuclei.

Question 27

The lateral geniculate nuclei relay signals in the optic tract to where?

Answer 27

to primary visual cortex (V1) via the optic radiation.

Question 28

What does the lateral geniculate nuclei control?

Answer 28

the amount of signal transmitted to the visual cortex according to the feedback.

Question 29

The signal transmitted from the lateral geniculate nuclei causes what?

Answer 29

feedback information from the visual cortex.

Question 30

feedback information processed by the visual cortex is carried by what?

Answer 30

corticofugal fibers.

Question 31

What do corticofugal fibers do?

Answer 31

regulate (inhibit) the actions of lateral geniculate nuclei.

Question 32

Signals from the reticular formation of the midbrain inhibit what?

Answer 32

the actions of lateral geniculate nuclei.

Question 33

What causes the visual system to focus on important signals?

Answer 33

The feedback information from the visual cortex and reticular formation.

Question 34

The auditory system transmits signals through the lateral geniculate nuclei to do what?

Answer 34

directly focus visual system on source of sound.

Question 35

Magnocellular M cells of the lateral geniculate nucleus do what?

Answer 35

receive and transmit signals from Y or M retinal ganglion cells.

Question 36

Magnocellular M cells respond to what?

Answer 36

Rapid changes in visual image.

Question 37

Magnocellular M cells transmit information about what?

Answer 37

black and white vision only.

Question 38

Parvocellular P cells of lateral geniculate nucleus are what?

Answer 38

receive and transmit signals from X or P retinal ganglion cells.

Question 39

The P cells transmits what?

Answer 39

color vision.

Question 40

P cells transmit fine details of what?

Answer 40

visual image.... accuracy of image.

Question 41

What are Koniocellular K cells of lateral geniculate nucleus?

Answer 41

are neurochemically distinct from M and P cells.

Question 42

The K cells in the two most dorsal of koniocellular layer transmit what?

Answer 42

low visual acuity signals to primary visual cortex.

Question 43

The K cells in the middle pair layer transmit what?

Answer 43

signals from blue cones to color blobs in primary visual cortex.

Question 44

The K cells in the ventral layers do what?

Answer 44

Participate in superior colliculus function.

Question 45

The Y or M retinal ganglion cells precept exclusively to what structure?

Answer 45

to magnocellular layers of lateral geniculate nucleus.

Question 46

The X or P retinal cells precept exclusively to what structure?

Answer 46

to the parvocellular layers of the LGN

Question 47

The K retinal ganglion cells project exclusively where?

Answer 47

to koniocellular layers.

Question 48

Do not confuse M,P,or K retinal ganglion cells with what?

Answer 48

M,P, or K neurons of the lateral geniculate nucleus.