Unit 2 Visual System

Question 1

Receptive field of ganglion cell

Answer 1

Circular!
2 types:
1. On-center (+ response to light at center w/ dark periphery)
2. Off-center (+ response to light at periphery w/ dark center)

Question 2

Lateral geniculate nucleus (and vision)

Answer 2

6 layered structure (increase # from inside-out), in thalamus;
– “magnocellular” = layers 1-2; “Parvocellular” = layers 3-6
* has on-center/off-center (“center-surround”) receptive fields!
==> for conscious visual perception relay
** = retinotopic map!, “sees” contralateral visual hemifield

Question 3

Magnocellular ganglion cells ***

Answer 3

type of retinal ganglion cell (larger, w/ large dendritic fields –> large RFs)
- fast conducting, no color sense,

Question 4

optic radiations

Answer 4

neural pathway connecting LGN to primary visual pathway,
2 parts: (separated by calcarine fissure)
1. Meyer’s Loop: info from inferior retina (superior VF), travels inferiorly (passes through temporal lobe)
2. Superior optic radiations: info from superior retina (inferior VF)