L16 - Parallel channels - Physiology, LGN (TV)

Question 1

The M and P channels remain segregated until?

Answer 1

PVN

Question 2

How many layers in Parvo layer? Magno?

Answer 2

Parvo - 4 Layers 3-6

Magno -2 Layers 1-2

Question 3

Contra or Ipsilateral - the 6 layers of LGN

Answer 3

P6 - C
P5 - I
P4 - C
P3 - I
M2 - I 
M1 - C

Question 4

Where are Koniocellular layers located?

Answer 4

Ventral to each parvocellular and magnocellular layer of the LGN.

Question 5

ON-centre cells responds to positive/negative contrast?

Answer 5

Positive

Question 6

OFF-centre cell responds to positive/negative contrast?

Answer 6

Negative

Question 7

T/F: Having both ON and OFF systems increases metabolic cost

Answer 7

FALSE

Question 8

Michelson contrast formula

Answer 8

(Max - Min)/(Max + Min)

Question 9

Contrast where you just detect a grating is aka?

Answer 9

Contrast threshold

Question 10

What is the reciprocal of contrast threshold?

Answer 10

Contrast sensitivity

Question 11

Spatial freq

Answer 11

How many cycles in one degree of visual space

*For gratings with 5 or 6 cycles per degree, we are highly sensitive to it

Question 12

As spatial frequency increases, it becomes harder to see

Answer 12

see

Question 13

Small bistratified cells

Answer 13

GC that carry signals from short wavelength-sensitive (blue) cones to the intercalated (koniocellular) layers of the LGN.

Question 14

We use Marmoset (new world monkeys) as the koniocellular layers are quite big (easier to observe)

Answer 14

We use Marmoset (new world monkeys) as the koniocellular layers are quite big (easier to observe)

Question 15

T/F: Koniocellular layer is only found in between layers

Answer 15

Also found in ridges

Question 16

What would respond to an isoluminant red/green stimulus? Red/green opponent cells are located in?

Answer 16

Parvocellular layer

*NOT magno (because stimulus is isoluminant) nor konio (because it responds to short wavelengths)

Question 17

What would respond to an isoluminant blue/yellow stimulus? Blue/yellow opponent cells are located in?

Answer 17

Koniocellular layer