Week 2 (ch 2&3)

Question 1

main route from retina to cortex

Answer 1

Retina
Lateral geniculate nucleus (lGN d )
primary visual cortex

Question 2

How many receptors in the cortex

Answer 2

95 million in each retina

Question 3

how many fibres in each optic nerve

Answer 3

1 million

Question 4

what are the areas in the retina called?

Answer 4

Parsal
midget
Bi-stratified

Question 5

What location in the LNG does PARSAL retina have?

Answer 5

Magno- cellular

Question 6

What location in the LNG does MIDGET retina have?

Answer 6

Parvo-cellular

Question 7

What location in the LGN does Bi-stratified retina have?

Answer 7

Konio- cellular

Question 8

What percentage does magno-cellular cells have?

Answer 8

10%

Question 9

What percentage does Parvo-cellular cells have

Answer 9

80%

Question 10

What percentage does Bi-stratified cells have?

Answer 10

less than 10%

Question 11

Which layers does mango-cellular cells occupy

Answer 11

Bottom 2 layers (one in each eye)

Question 12

Which layers does Parvo - cellular cells occupy?

Answer 12

Top 4 layers (2 in each eye)

Question 13

Which layer does Bi- Stratified cells occupy ?

Answer 13

Inner layer (3 in each eye)

Question 14

What is Spatial frequency ?

Answer 14

Number of repetitions of grating pattern in a fixed distance

Question 15

What does M cells respond to ?

Answer 15

They respond to a larger light receptive field - Respond to bigger things

Question 16

Which cell responds to rapid change?

Answer 16

M cells

Question 17

M-cells in regards to contrast

Answer 17

Larger axons

rapid signal transfer from retina to cortex

Question 18

P-cells in regards to contrast

Answer 18

bigger response at low contrast levels

has an linear increase