Visual Pathways - week 11

Question 1

Layers of LGN from Inner to outer?

Answer 1

Can I Imagine Cats In Canada (Contra, Ipsi, Ipsi, Contra, Ipsi, Contra)

First 2 layers are Magnocellular layers, next 4 are parvocellular layers

Question 2

What layer is between magnocellular and parvocellular layer?

Answer 2

Koniocellular layer

Question 3

Where do the parvocellular layers get input from?

Answer 3

Midget cells

Question 4

Where doe the Magnocellular layers get input from?

Answer 4

Parasol cells

Question 5

How large is the Magno receptive field?

Answer 5

Large

Question 6

Describe Magno contrast sensitivity?

Answer 6

High

Question 7

Describe Magno spatial resolution?

Answer 7

Low

Question 8

Which is better for detecting motion? Magno or Parvo?

Answer 8

Magno. Because it is a transient response

Question 9

How large is Parvo receptive field?

Answer 9

small

Question 10

Describe Parvo contrast sensitivity?

Answer 10

Lower

Question 11

Describe Parvo spatial resolution?

Answer 11

High spatial resolution

Question 12

Where does Magno project to?

Answer 12

Layers 4Calpha and lower 6 in area V1

Question 13

Where does Parvo project to?

Answer 13

Layers 4Cbeta and upper 6 in V1

Question 14

Which pathway mediates red/green colour vision? Magno or Parvo?

Answer 14

Parvocellular pathways

Question 15

Which pathway is best sensitive to motion? Magno or Parvo?

Answer 15

Magnocellular cells are sensitive to motion

Question 16

Which has faster conduction velocity? Magno or Parvo?

Answer 16

Magnocellular (because bigger myelin sheathe)

Question 17

What signals do Koniocellular cells carry?

Answer 17

Short-wavelength sensitive signals from the cones

Question 18

Which pathway is involved with blue/green discrimination?

Answer 18

Koniocellular pathway

Question 19

To which layers in LGN do parasol retinal cells project?

Answer 19

(= magnocellular pathway) so layers 1-2

Question 20

To which layers in LGN do midget rGCs project?

Answer 20

3-6

Question 21

What retinal ganglion cell type carries S cone signals? Which LGN regions do they project to?

Answer 21

Short bistratified

- project to koniocellular

Question 22

Which LGN layers transmit red/green signals?

Answer 22

3-6

Question 23

Which LGN layers transmit blue/yellow signals?

Answer 23

koniocellular

Question 24

What is blindsight?

Answer 24

Ability to respond to visual stimuli without consciously perceiving them (can occur after type of brain damage)

Question 25

What sort of visual field defect does a lesion in the optic chiasm cause?

Answer 25

Bitemporal Homonymous Hemianopia

Question 26

Which of the following pass through superior orbital fissure?
A) ophthalmic nerve
B) Oculomotor nerve
C) optic nerve
D) trochlear
E) abducencs
F) ophthalmic vein

Answer 26

Trochlear apparently