Primary Visual Cortex (V1)

Question 1

What lobe of the cerebral cortex is visual information processed?

Answer 1

occipital

Question 2

What type of nerve connects information from the optic nerve to the LGN?

Answer 2

Axon bundle (cable-like)

Question 3

What type of nerve connects information from the LGN to the visual cortex?

Answer 3

Optic radiation (fanning out)

Question 4

There are 10x as many nerve fibers going from V1 -> LGN or LGN -> V1?

Answer 4

V1 -> LGN

Question 5

V1

Answer 5

• first receiving area from LGN
• foundation for V2
• initial processing

Question 6

What side of V1 is left visual field information processed?

Answer 6

Right V1

Question 7

What side of V1 is right visual field information processed?

Answer 7

Left V1

Question 8

At the optic chiasm what is crossing over?

Answer 8

• Right Visual Field (left side of eye) from OD
• Left Visual Field (right side of eye) from OS

Question 9

Grey Matter

Answer 9

neurons/cell bodies, folded sheets, local axon branches only

Question 10

White Matter

Answer 10

axons making long-range connections, no signaling back and forth

Question 11

sulcus

Answer 11

fold

Question 12

Cortical Magnification

Answer 12

Central Field = huge (RGC density higher)
Peripheral Field = small (RGC density lower)

Question 13

Monocular Blindness

Answer 13

One eye has a lesion on the optic nerve (loss of entire eye)

Question 14

Bitemporal Hemianopsia

Answer 14

Loss of OS (Left VF) and OD (Right VF), lesion at optic chiasm, no crossing over

Question 15

Homonymous Hemianopsia

Answer 15

Loss of Visual Field in either left or right in both eyes, Right Optic tract lesion = complete left VF loss in both, Left Optic tract lesion = complete right VF loss in both

Question 16

Foveal Sparing

Answer 16

Lesions in optic radiation leave fovea information preserved since it is hard for a lesion to stop all foveal fibers

Question 17

Magnocellular layers connect to what part of the cortical V1?

Answer 17

IVC(alpha)

Question 18

Parvocellular layers connect other what part of the cortical V1?

Answer 18

IVC(beta)

Question 19

Binocular vision or fusing of images from both eyes occurs at what layer of the cortical V1?

Answer 19

II, III

Question 20

Is IVC(alpha) above or below IVC(beta)?

Answer 20

above

Question 21

Simple Cell

Answer 21

• distinct zones of excitation/inhibition
• linear weighted sum
• position oriented

Question 22

Complex Cell

Answer 22

• orientation selective
• no dependent on location
• recognize shapes better
• non-linear response

Question 23

Hypercomplex Cell

Answer 23

• combining complex cells