Vision 1 Flashcards
What lobe is in charge of visual processing and where is it located?
The occipital lobe + it is located in the back of the brain.
What is the sense that has the most “real estate in the brain” in humans and in mice?
In humans, vision. In mice, smell.
What we perceive is the same as the physical input coming in from the world.
False, at times we perceive things a certain way when it is not actually like this.
What is the pathway for light to vision?
light –> cornea –> pupil –> lens –> retina –> through ganglion and bipolar cells –> rods and cones
What is the center of the retina called? (hint: it also contains the most cones)
fovea
What is the optic nerve composed of?
Axons of ganglion cells that bundle together
What is the optic disk?
It is the blind spot in the retina, created by the bundle (optic nerve)
What are some basic characteristics about cones?
They are more concentrated at the fovea, more active during the daylight, color is perceived when the three different kinds of cones differ in firing activity.
What are some things to know about rods?
They are distributed all over the retina, they are important in low levels of light, they are sensitive to black/white and movement.
How does visual acuity differ between rods and cones?
Each cone directly connects to ganglion cells, giving good spatial localization and detail but is not good during low levels of light. Each rod, however, has various rods connected to a single ganglion, which helps with seeing during low light but has poor detail and spatial localization
Color is perceived in terms of opposites, which pairs are these?
red + green, blue + yellow
What do the ganglion cells send along the optic nerve?
Action Potentials
”Red” and “Green” cones connecting to the same
bipolar cell produce sensitivity to which color?
yellow
90% of visual information is transmitted to which brain region?
lateral geniculate nuclei in the thalamus
Information travels from retina to
the brain via the ________ ______,
crossing at the _____ _______
optic nerve, optic chiasm
magnocellular cells characteristics
faster, coarse, movement, depth
parvocellular cells characteristics
slower, form, green/red, fine details
koniocellular
blue/yellow
What are some other visual pathways?
retina –> superior colliculus in the midbrain, retina –> hypothalamus
How is V1 (primary visual cortex) organized?
Retinotopically
How is visual information projected to V1 (anteriorly or posteriorly)?
Anteriorly
As we move forward from V1 to
subsequent visual areas:
1) Neurons respond to more
and more complex information
2) Receptive fields of neurons
get larger and larger
What section shows textures?
V4
