iClicker Module 7 Flashcards
In theatre, they use gels to cover the lights to change their hue. What wavelength of light would pass through a blue gel creating a blue spotlight?
Only blue light (400-475 nm)
If I stole all of the theatre lights and used a different gel on each one and pointed them all to the center of the stage what color would the spot be?
White
Yes or No: Some people have corneas that are more rounded while others have corneas that are more oblong (football shape). Does this difference in curvature influence their visual acuity?
Yes
When you go to the ophthalmologist, they may put drops in your eyes so they can look at the back of your eye (also called a fundus). Why do they suggest you wear sunglasses afterward?
Because the drops dilated your pupils allowing too much light into your eye
Which structures influences the path of light before it hits the retina?
Cornea
Aqueous Humor
Lens
Vitreous Humor
What would happen to your vision if your unaccommodated lens caused the light to focus PAST the retina?
Farsightedness (can’t see up close)
Why do people squint when they have a hard time seeing something?
Squinting can change the shape of your eye
-Force your eye to be more oblong (less round)
If the crystalline structure of the lens becomes disrupted, it becomes opaque (less transparent). How would this influence your vision?
It would make everything harder to see
Light travels through which part of the eye first?
Cornea
Which photoreceptors are specialized for low light situations?
Rod
Which form of electromagnetic radiation causes skin cancer AND can be detected by insects?
UV light
Which area of the retina has the highest concentration of cone photoreceptors?
Fovea
Each cone photoreceptor has a different opsin. Red cone photoreceptors do what?
Transduce red light
Which of the following statements is false about the transduction of light?
-Light stimulates the opsin
-Secondary messenger cascade triggers hyper polarization by closing sodium channels
-Retinal opens sodium channels depolarizing the neuron
-The amount of neurotransmitter released is proportional to the amount of photons detected
Retinal opens sodium channels depolarizing the neuron
Which retinal cell type is important in lateral inhibition?
Horizontal cell
Which retinal cell type transduces light?
Photoreceptor
Which retinal cell sends information to the brain via the optic nerve?
Ganglion cell
What cell type of cell pools information allowing your visual system to be more sensitive?
Diffuse Bipolar cell
Within the fovea, each cone photoreceptor synapses with…
both on & off bipolar cells
Within the fovea, each midget bipolar cell synapses with how many and what kind of ganglion cell?
A single P ganglion cell
What is the function of an amacrine cell?
The precise function is unclear
Which type of ganglion cell makes a larger contribution to visual acuity (smallest spatial detail that you can see)?
P ganglion cells
If light hit the periphery of the receptive field of an ON-center ganglion cell. What would happen to its firing rate?
Decrease
If the light hit the center of the receptive field of an ON-center ganglion cell. What would happen to its firing rate?
Increase
Yes or No: Is your ability to perceive spatial details better if you look at it with your peripheral vision?
No
Your fovea has the most number of cones
Coming into one input, making peripheral bad compared to center
How would an on-center ganglion cell of respond (relative to any other time with the moving bars) when the light is only in the center?
Increase in firing rate
(positive response)
How would an on-center ganglion cell of respond (relative to any other time with the moving bars) when the light is only in the periphery?
Decrease in firing rate
(negative response)
How would an on-center ganglion cell of respond (relative to any other time with the moving bars) when the light is between center and periphery?
No change/ in the middle
(no response)
Retinal ganglion cells directly innervate which brain region?
Lateral Geniculate Nucleus
Which layer of the lateral geniculate nucleus receives input from the fovea?
Parvocelllular layer
Which layer of the geniculate nucleus receives input from the diffuse bipolar cells?
Magnocelluar layer
Why is the fovea representation of the cortex so magnified? Why not be able to see the entire visual field with high resolution?
Too much for your brain
Your brain fills in the edges of objects considered to be the foreground. These edges are called what?
Illusory contours
How did you learn to classify objects? How is it similar or different from machine learning?
We learn to understand individual species and groups through key features
In which brain region, would you find neurons that respond specifically to a location?
Parahippocampal place area
In what brain area region, would you find neurons that respond specifically to objects or faces?
Inferotemporal cortex
In which brain region, would you find neurons that respond only to object features (i.e. edges) but not the entire object?
Primary visual cortex (V1)
If you suffered from agnosia, which brain region might be damaged?
Inferotemporal cortex
What is color vision good for?
Recognizing food sources
-visually perceive ripeness of a fruit
Recognizing danger
-poisonous animals or foods
Social cues
-blushing, redness of lips, paleness, etc.
Why is the sky blue?
The atmosphere reflects 400 nm (blue) light
How do we detect color?
Three different types of cone photoreceptors
Why don’t we have one broadly tuned cone photoreceptor?
Everything would be the same color
Wouldn’t be able to discriminate between different wavelengths
-the amount of receptors responding would be the same
Which of the following scenarios would result in the perception of yellow?
Equal stimulation of M-cones (green) and L-cones (red)
Which of the following scenarios would result in the perception of cyan?
Equal stimulation of S-cones (blue) and M-cones (green)
If RGB is so important, why did my art teacher tell me that yellow is a primary color and why does my printer take C, M, Y, K?
Mixing pigments is different
Add more light, you change the color
Additive colors- lights
Subtractive colors- paint
So called “impossible colors” are colors that don’t appear in normal vision. Which one of the following is an impossible color?
Reddish Green
-It will turn into yellow
-B/c our color opponent cells
If an animal has two eyes that are closer together. What can you infer about that animal’s trophic level?
Carnivore and Insectivore
-have to be able to see and catch their prey
-herbivores don’t have to worry about a plant moving
Yes or No: If an object is very close to your face, will it have a large binocular disparity?
Yes
-zero on the Horopter
Which monocular depth cue is allowing us to gauge that
Which monocular depth cue is allowing us to gauge that the orange slice on the right is closer to us?
Occlusion
Which monocular depth cue is allowing us to gauge that end of the hall is pretty far away?
Linear perspective
Which monocular depth cue is allowing us to gauge that this city is still pretty far away?
Atmospheric Occlusion
Which of the following situations could be used to explain the aperture problem?
-Viewing motion at low light levels
-Viewing only part of the motion through a small viewing window
-Watching cartoons at really slow speeds
-Moving your head while watching an object in motion
Viewing only part of the motion through a small viewing window
Which of the following brain regions/structures are involved in perceiving motion?
Photoreceptors
-what detects the light overall, detecting motion
Ganglion cells
-on cells and off center cells
Primary Visual Cortex
-responding to the motion
Middle Temporal Area
-global motion detector
What is the current thought regarding how the brain deals with the aperture problem?
Combine the different receptive fields using a global motion detector
What would happen to someone who had a stroke, damaging their middle temporal area of the cortex?
They would be blind to the motion of objects
Which monocular depth cue is being used to inform us that the T-Rex is really big?
Size or position
-comparing the size of the car/ things next to it
Neurons in this structure respond robustly to moving gratings of a particular size (i.e. the width of the light and black portions) but don’t respond differentially according to direction, borders, border ownership, or shapes, and don’t have the ability to extract genuine motion?
Retina
Neurons in this structure respond differently according to direction, border ownership, and shapes, but don’t have the ability to extract genuine motion?
Extrastriatal cortices
Neurons in this structure respond specifically to faces
Fusiform face area
Which of the following is NOT a basic principle our visual system uses to assign an object to the figure or ground?
-Size
-Relative motion
-Parallelism
-Surroundedness
-Color
Color
-Size= the smaller object tends to be the one in front
-Surroundedness= object surrounded by something else
-Parallelism= things go together, in front
-Relative motion
What is Binocular disparity?
The difference in the location an object appears on the retina of your two eyes
Which monocular depth cue highlights that the mountains are really far away?
Atmospheric occlusion
What is a grandmother cell?
A cell that responds to a particular concept (like an individual)
What is the correspondence problem?
The challenge of determining which parts of the two retinal images come from the same object
Which of the following situations could be used to explain Aperture problem?
Viewing only part of the motion through a small window
What is the current thought regarding how the brain deals with the Aperture problem?
Combines the different receptive fields using a global-motion detector
A cartoon is a good example of this type of motion?
Apparent motion
This portion of the eye focuses the incoming light onto your Retina?
Lens
This portion of the eye regulates the amount of light entering your eye.
Iris
In an invertebrate eye, light will come in contact with which of the following structures first?
Photoreceptor
For a vertebrate eye, Ganglion cell
