Visual Pathways

Question 1

What is the general Visual Pathway

Answer 1

Retina> Optic Nerve> Optic chiasm> optic tract> LGN> Optic radiations> Visual cortex> Visual Association Areas

Question 2

What are the 1st order neurons

Answer 2

Photoreceptors

Question 3

What is the job of photoreceptors

Answer 3

Phototransduction

Question 4

What are the 2nd order neurons

Answer 4

Bipolar, horizontal, amacrine cells

Question 5

What is the uprise of 2nd order neurons

Answer 5

Process, modify, relay the signal to ganglion cells

Question 6

What are the 3rd order neurons

Answer 6

Retinal ganglion cells

Question 7

What is the job of the 3rd order neurons

Answer 7

Process/modify the neural signal

Relay it to higher structures

Question 8

Look over drawin of the visual fields

Answer 8

Binder

Question 9

The axons make a ____ degree angle to leave the eye

Answer 9

90

Question 10

What increases the diameter of the retrobulbar optic nerve

Answer 10

Myelin

Question 11

What are the 4 divisions of the optic nerve

Answer 11

Intraocular
Intraorbital
Intracanalicular
Intracranial

Question 12

Do temporal fibers cross over in the optic chiasm?

Answer 12

No

Question 13

Do nasal fibers cross over in the optic chiasm?

Answer 13

Yes

Question 14

What are the 3 layers of the LGN

Answer 14

Magnocellular (layers 1-2)
Parvocellular (layers 3-6)
Koniocellular (sublayers 1-6)

Question 15

A lesion of the inferior optic radiation in the left temporal lobe appears as this

Answer 15

Right superior quadrantanopsia

Question 16

A lesion of the superior optic radiations in the left parietal lobe appears as this

Answer 16

Right inferior quadrantanopsia

Question 17

The cuneus gets what projections

Answer 17

The superior fibers

From the inferior VF

Question 18

What radiations does the lingual have

Answer 18

Inferior projections from the superior visual field

Question 19

The dorsal stream has what info

Answer 19

“Where”

Question 20

The ventral stream has what info

Answer 20

“What”

Question 21

What is a consensual pupillary response

Answer 21

If you shine a light in one eye the other eye should also constrict

Question 22

What blood structure supplies the visual system

Answer 22

Circle of Willis

Question 23

What is macular degeneration

Answer 23

It’s a disease of the of the back of the eye that affects there central vision. The RPE is getting sick and there is a buildup of metabolic wastes and the cells are getting sick and breaking down. The blood vessels grow in and leak fluid/blood. Causes angiogenesis. Given anti-VEGF to keep these blood vessels ar bay.

Question 24

What is retinitis pigmentosa

Answer 24

A degeneration of the rods in the retina. It starts in peripheral and works centrally. Bone spicules form. Causes tunnel vision.

Question 25

Look through the lesions and the visual defects they cause

Answer 25

Binder

Question 26

The corticobulbar pathway processes what

Answer 26

Voluntary motor pathways

Question 27

Where does the voluntary motor pay project to

Answer 27

Pons and medulla

Question 28

Accommodation process

Answer 28

1. Retina
2. Area 17
3. Area 19
4. Pretectal nucleus
5. EW nucleus
6. Preganglionic parasympathetic neurons
7. Sphincter pupillae

Question 29

Light reflex process

Answer 29

1. Retina
2. Area 17
3. Optic tract to pretectal nucleus
4. EW nucleus
5. Preganglionic parasympathetic neurons
6. Sphincter pupillae

Question 30

Pupillary dilation process

Answer 30

1. Posterior hypothalamus
2. Ciliospinal center of budge
3. Superior cervical ganglion
4. Ophthalmic pleas
5. Dilator pupillae

Question 31

What are Horner Sydnrome symptoms

Answer 31

Pupil constriction
Ptosis
Skin redness
Facial anhydrosis

Question 32

What CN run through the cavernous sinus

Answer 32

3, 4, V1, V2