Visual system 11/18/16

Question 1

What allows visual pathway lesions to produce predictable visual field deficits?

Answer 1

Retinotopy

Question 2

What is the first structure light goes through on its way to the eye?

Answer 2

-Cornea

Question 3

What is the cornea innervated by?

Answer 3

-Trigeminal

Question 4

Where does the majority of refraction of light occur?

Answer 4

-Cornea

Question 5

T/F

The lens bends light more than the cornea.

Answer 5

False

-The cornea bends light more than the lens

Question 6

What is the anterior chamber filled with?

Answer 6

-Aqueous humor

Question 7

What nourishes the cornea and lens?

Answer 7

-Aqueous humor

Question 8

T/F

The vitreous body is a protein rich fluid

Answer 8

True

Question 9

What keeps the retina pinned back against the back of the eye?

Answer 9

-Viterous body

Question 10

What controls the fibers of the lens that allow tension of the the lens?

Answer 10

-Ciliary body

Question 11

What is the first place in the retina that light goes through?

Answer 11

-Ganglion cells

Question 12

What in the retina is used to process vision first in the retina?

Answer 12

-Internal nuclear ganglia

Question 13

What is the name of the one type of glial cell in the retina?

Answer 13

-Muller cell

Question 14

What are the three types of cones that humans have?

Answer 14

• Red
• Green
• Blue

Question 15

Where do you find most rods in the eye?

Answer 15

-Periphery

Question 16

What cells are the only ones in the retina that can fire action potentials?

Answer 16

-Ganglion cells

Question 17

Where do you find the fovea?

Answer 17

-In the center of the macula

Question 18

Where do you have your high acuity vision?

Answer 18

-Fovea

Question 19

Is there more cones or rods in the fovea?

Answer 19

-Cones

Question 20

What part of the retina does night vision?

Answer 20

-Peripheral retina

Question 21

T/F

Axons for temporal visual fields cross to contralateral side

Answer 21

True

Question 22

T/F

Axons for nasal visual fields cross to contralateral side

Answer 22

False

-Nasal stay ipsilateral

Question 23

If you have a tumor pressing on the optic chiasm what type of vision do you lose?

Answer 23

-Peripheral vision

Question 24

Where do inputs from both eyes come together?

Answer 24

-After the optic chiasm

Question 25

T/F | Peripheral vision from the left eye runs to the right side of the brain

Answer 25

true

Question 26

What is the structure in the thalamus that handles visual information

Answer 26

Lateral geniculate nucleus

Question 27

What three lobes of the brain does vision pass through at some point?

Answer 27

- Temporal - Parietal - Occipital

Question 28

If you look up towards the sky and the image is processed in the brain is it higher or lower in the brain?

Answer 28

-Lower

Question 29

What visual field does the temporal lobe carry?

Answer 29

-Upper visual field

Question 30

What visual field does the parietal lobe carry?

Answer 30

-Lower visual field

Question 31

What separates the upper and lower field in the occipital lobe?

Answer 31

-Calcarine sulcus

Question 32

Where does the first visual synapse occur?

Answer 32

-Lateral geniculate nucleus

Question 33

T/F There is a map of visual space on the primary visual cortex where the macula is extremely small because of its size in the retina

Answer 33

False | The macula is larger because it is a main component of vision

Question 34

What is the blood supply to the calcarine cortex?

Answer 34

-Posterior cerebral artery

Question 35

What is the blood supply to the LGN and optic tract?

Answer 35

-Anterior chorodial artery

Question 36

If you have a lesion of the optic nerve on the left eye what occurs?

Answer 36

-Blind left eye

Question 37

If you have a lesion on the lower bank of the calcarine sulcus what occurs to your vision?

Answer 37

-You lose upper vision

Question 38

Where do the fibers coming in from the pupillary light reflex go?

Answer 38

-Pretectal region

Question 39

What nucleus do the fibers of the pupillary light reflex go?

Answer 39

-Edinger-Westphal nucleus

Question 40

T/F | A tumor of the pineal gland can cause a loss of the pupillary light reflex

Answer 40

True

Question 41

What allows the pupillary light reflex to be consensual?

Answer 41

-The interneurons that carry the info to the E.W. nucleus on both sides

Question 42

If you have a subdural hematoma with uncal herniation that involves CN III what occurs?

Answer 42

- Sluggish or absent pupillary reflex - Ptosis - Less effects on extraocular movements

Question 43

What causes pupillary dilation?

Answer 43

-Sympathetic pathway

Question 44

The start of the neurons in the sympathetic pathway that causes pupillary dilation originate where?

Answer 44

-Hypothalamus

Question 45

From the hypothalamus where does the 1st order sympathetic neuron go?

Answer 45

T1

Question 46

From the synapse at T1 in the sympathetic pathway where does the second order neuron go?

Answer 46

-Superior cervical ganglia

Question 47

From the superior cervical ganglia where does the 3rd order sympathetic neuron travel?

Answer 47

-Pupil

Question 48

What part of the brain is used in the voluntary fast horizontal eye movements?

Answer 48

-Frontal eye field on the frontal lobe

Question 49

What does the left side of the visual cortex control?

Answer 49

-Right field of vision

Question 50

Where do cells in the fontal eye field project to?

Answer 50

-Contralateral PPRF

Question 51

From the PPRF where do the neurons go?

Answer 51

-CN VI (Abducens nucleus)

Question 52

From the Abducens nucleus where do neurons go?

Answer 52

- Lateral rectus | - Oculomotor nucleus

Question 53

After the abducens nucleus sends a neuron through the MLF to the oculomotor nucleus where does the neuron go?

Answer 53

-Medial rectus

Question 54

What do PPRF lesion s lead to?

Answer 54

-Horizontal gaze paralysis of both eyes, toward the side of the lesion

Question 55

If you have a lesion of the MLF what occurs to your vision?

Answer 55

-You'll have double vision

Question 56

What is a lesion in the visual pathway in the MLF called?

Answer 56

-Internuclear Ophthalamoplegia

Question 57

What disease is Internuclear Opthalamoplegia a possible sign of?

Answer 57

-MS

Question 58

T/F | With a pineal tumor you can lose upward gaze

Answer 58

True