Vision Flashcards
The cones are concentrated in the ________________
Central Fovea
What is Foveation?
When the eyes focus on one object, the rest of the things around get blurred.
The fovea centralis being the portion of the retina responsible for sharp central vision.
Vision is not continuous. The brain puts together a continuous visual experience from a sequence of ____________ and ____________
Fixations and Saccades
Vision is not continuous. The brain puts together a continuous visual experience from a sequence of ____________ and ____________
Fixations and Saccades
Since ________________ vision is blurry because the eyes are moving, this information is often ignored.
Saccadic
Eye tracking Research is done through _______________
Occulometers
What is RSVP?
Rapid Serial Visual Presentation.
It requires participants to look at a continuous presentation of visual items which is around 10 items per sec. They are all shown in the same place.
What is the relevance of Foveation and Eye Tracking?
Design to minimize the visual work in scanning the diaplays.
Websites are scanned with ____________
F- shape
People first tend to scan :
- Complex Areas
- Saturated colors
- Dark Areas
- Human Faces
Can text color affect user interaction?
Yes to highlight certain heading or to draw attention to particular text, changing the text color helps.
Why are we drawn to faces?
- There is a special part of brain just for recognizing faces. The Fusiform Face Area (FFA) of our brain allows us to identify faces faster than objects. FFA lies very near to the Amygdala which is the brain’s emotional center.
- The eyes are very important. People look at the eyes and decide if the picture shown to them is of someone who is human and alive.
While choosing a human face for a landing page/advertisement, what should you keep in mind?
When photos of real people are presented with content, they are automatically treated as important.
Users are immediately drawn to a face but if the face is looking in another direction they also tend to pay attention in that direction.
We need to decide whether there is need to establish emotional connection (face looking right at the user) or direct their attention (face looking at product).
What is the relevance of visual scan prediction?
People tend to scan based on their expectations. you need to understand what they expect and design to support their expectations.
You can draw the user’s attention to a location with
- Complex Areas
- Saturated Colors
- Dark Areas
- Human Faces
What is Perceived Size?
How well you can see something depends on how far it is and how big it is.
Distance/ 200
What is the optimal reading speed?
17 minutes of Arc
What is startle response?
Attention is directed to any sudden movement, sound or other sensation.
It results in arousal of the Sympathetic Nervous System and reduction in Parasympathetic Nervous System activity.
How often should you use motion?
- Limit the use of animation of all kinds.
* Avoid wiggly stuff.
What is the relevance of Stroop Effect?
- Maintain consistency with color.
- Do not have clashes between color and its meaning.
- Use only the color codes the people expect. (Eg. writing Stop in green, will not have the same impact)
_______________ test is for color Blindness
Ishihara
What is Purkinje Shift?
sensitivity of the human eye to shift towards the blue end of the spectrum at low illumination levels.
this effect introduces a difference in color contrast under different levels of illumination.
What is Chromatic aberration?
It is an effect resulting from dispersion in which there is a failure of a lens to focus all colors to the same convergence point. It occurs because lenses have different refractive indices for different wavelengths of light.
What is chromostereopsis?
Pure Blue Text on Pure Red Background or vice-versa should never be used because it generates chromostereopsis i.e. depth through color perception and causes reading difficulty.
What is small field Tritanopia?
If the stimuli are made sufficiently small, color normal individuals report a loss in hue perception, in particular a decrease in the perception of green, in both the fovea and peripheral retina. This is called small field tritanopia.
How to ensure color and legibility?
- Always design monochrome and add color to enhance.
- make sure there is enough contrast.
- Avoid pure blue on pure red or red on blue or red/blue on black.
What is canonic perspective?
It is the expected form - It is the standard or preferred way of viewing an object.
What is the relevance of canonic perspectives?
Easy to recognize icons and graphics - When creating graphics or icons make sure you are using the canonic perspectives that people expect.
why is Pattern Recognition important?
Pattern recognition is critical to identifying objects, moving through space, reading a book, looking at art.
