Visual System Part 2 Flashcards
Retinal ganglion cells axons leave the retina through ___________ and project to the _____________.
Optic nerve
Lateral geniculate nucleus (LGN)
Axons from retinal ganglion cells in the _______________ remain on the same side of the brain and synapse on cells in the ____________(same side) LGN.
Temporal half
Ipsilateral
While cells in the ________ half of the retina cross the midline and synapse on cells in the __________ (other side) LGN.
Nasal
Contralateral
What axons are involved when you see an image on the left visual field?
Hint: What side of the eyeball is involved?
* same for the right visual field
Temporal side of the right eye
Nasal side on the left eye
Information from the (left/right half) of the visual field from both eyes goes to the (left/right side) of the brain
While information from the (left/right) half of the visual field from both eyes goes to (left/right) half of the brain.
Information from the left half of the visual field from both eyes goes to the right side of the brain
While information from the right half of the visual field from both eyes goes to the left half of the brain.
How is the information kept in the LGN?
In layers
Different species have different exact numbers and arrangements of LGN layers. How many LGN layers does a human have?
___ receiving information from each eye.
6 layers
3
True or False: The cells in the LGN have different receptive fields to those of the retinal ganglion cells (RBCs).
They both have center-surround receptive fields.
False
Receptive fields are very similar to the retinal ganglion cells
The second half is true.
Looking at the figure
Which one of these receptive fields will stimulate the strongest action in the On-center ganglion cells?
The first one because the light shines in the middle of the ganglion cell,
which is similar to the Lateral Geniculate Nucleus receptive field
Choose the best option
LGN cells receive (little/various) inputs from RGC
LGN’s receptive field is a bit (more/less) sophisticated
Various
More
What are the various receptive fields that the LGN received?
Hint: There are three receptive fields.
Respond to different wavelengths of light
Broadband center-surround cells
Respond to specific wavelengths of light
Red/green color opponent center-surround cells
Blue color opponent cells
_______________________ (Hint: one of the LGN receptive fields)
receive inputs from both red and green cones but are “color blind” and respond only to light-dark differences.
Broad-band center-surround cells
Which LGN receptive field responds over a broad range of wavelengths?
Broad-band center-surround cells
Answer these fellow examples of broad-band center-surround cells’ receptive fields. Here let’s focus on the on-center field.
If there is a central spot in the on-center field–> ______________.
If there is a peripheral spot in the off area –> _________________.
If there is a central illumination in the on-center field –> _______________.
If there is surround illumination in the off area –> ________________.
If there is a diffuse illumination –>___________________.
Look at image for answer
Answer these fellow examples of broad-band center-surround cells’ receptive fields. Here let’s focus on the off-center field.
If there is a central spot in the off-center field–> ______________.
If there is a peripheral spot in the on area –> _________________.
If there is a central illumination in the off-center field –> _______________.
If there is surround illumination in the on area –> ________________.
If there is a diffuse illumination –>___________________.
What are the three parallel pathways (the different types of ganglion cells and pathway to LGN) of the primate retinal ganglion cells?
Parvocellular
Magnocellular
Koniocellular
True or False: These parallel pathways cross pathways and receive information from both eyes
False
Parallel pathways never cross pathways and receive information from left and right eye
Choose the best option
Parvocellular parallel pathways
(Small/large) cells
(Small/Large) receptive fields
(Is/Not) Color sensitive
(sustained/transient) response ; (slowly/rapidly) adaptation
Signal (Form and Details/Motion)
Small cells
Small receptive fields
Is Color Sensitive
Sustained response; slowly adaptation
the signal form and detail
Choose the best option
Magnocellular parallel pathways
(Small/large) cells
(Small/Large) receptive fields
(Is/Not) Color sensitive
(sustained/transient) response ; (slowly/rapidly) adaptation
Signal (Form and Details/Motion)
Large cells
Large receptive fields
NOT Color Sensitive
Transient response; rapidly adaptation
the signal Motion
Choose the best option
Koniocellular parallel pathways
(Small/large) cells
(Is/Not) Color sensitive
Small cells
Don’t know if it color -sensnitive
True or False: Different RGC types maintain sperate pathways through the lateral geniculate and visual cortex, while also respecting eye-specific pathways.
True