Lecture 5 - Attention and Eye Tracking Flashcards
What is the Simon Effect?
A concept
Like reverse controls in a game
Turn right and car goes left
annoying mario kart thing weird thing
consistent representations are easier to compute
faster to respond to consistent representations
incompatibilities tax attention
What is an automatic process?
A process that is instigated without conscious effort / control .
dont require cognitive resources
What is a controlled process?
A process that is voluntarily undertaken to meet a goal
Requires cognitive resources
What are both automatic and controlled processes important in?
Attention
What theorys are automatic?
Feature integration theory (segmentation of env features), treisman (sensory buffer store and attenuating filter) broadbent (sensory buffer store and selective filter)
Stroop task (automatic interfering w controlled processes Schneider & Schiffrin)
What theorys are controlled processes?
Broadbent’s higher level processing &wm??
Treismans Dictionary Unit and WM?
Feature Theory Attention part
What can automatic processes interfere with?
Controlled voluntary processes
With enough practice, controlled processes can become what?
Automatic
Attending to multiple features at once requires high cognitive resources
what is harder than the other
Conjunctive search is harder than parallel search
What is the cornea?
Responsible for around 70% of the focusing of the light to the retina at the back of the eye
What we see as the white of the eye.
Window allowing light to come into the eye
What components in the eye are responsible for adjusting light that comes through the eye so it falls on the retina?
Cornea, Pupil, Lens, muscles surrounding the lens
What is the pupil?
The hole in the middle of the Iris.
Pupil dialates or constricts depending on the amount of light that comes from the environment
eg, in dim light, the pupil dilates to allow more light to come in so we can see better. in bright light, pupil constricts letting less light in
can also dilate due to emotional responses
What is the Lens?
Allows us to focus the eye into the retina (back of the eye)
What are the muscles surrounding the lens?
Lens adjusters
Compresses or extends to allow light to focus
Responsible for 30% of the focusing on the light on the retina
Amount of change in the lens depends on the distance of eye to object
closer to object, lens muscles change shape of lens to allow light to focus more
What is the Retina?
Element that begins transforming light info into the brain
What is the Fovea?
Part of the retina with the highest aquity and highest amount of detail
What are the retina and fovea responsible for?
Converting light into electrical (neural) signals to transmit to the brain
How does electrical signals get transported to the brain?
Through the Optic Nerve -
The optic nerve transports electrical signals to the brain for processing
Particularly the occipital lobe, the visual cortex
How does an image/stimuli get perceived by the eye?
Process it takes
CPLROB
Cornea (focuses 70%)
passes thru pupil
passes thru lens and muscles, muscles change shape of lens depending on distance of the object for best focusing (responsible for 30%)
Object gets inverted when projected to the retina
goes thru optic nerve as an electrical signal to the brain which corrects the image
What does the retina contain?
2 types of photoreceptors
Rods and Cones
What are Rods responsible for and where are they found?
Low level vision: Vision in dim lights, low spatial resolution
Found in retina
What are Cones responsible for and where are they found?
High level vision: Vision at higher light levels, high spatial resolution
colour perception active at visions at higher light levels
What photoreceptor reacts more quickly in the dark than the other?
Cones react quickly, rods need more time adjusting that’s why it takes longer time for people to adjust to light in the dark
Rods do not have enough info from light to the brain so they need that
Cones always have light… and have higher spatial resolution
What is the Fovea in terms of visual acuity on the retina?
Has the area of the highest visual acuity on the retina
Large amount of cones
Low amount of rods
Where is high spatial resolution in our central vision found?
The area focused on the fovea
Where is poorer resolution found in?
Our peripheral vision
What is overt attention?
Attending to what our eyes are looking at
we use this in eye trackers bc we can see what the subject is directly looking at
What is covert attention
We can attend to info that are in our peripherals
How big is the visual area covered by the fovea?
Size of a thumbnail at arms length
Fovea can focus on the equivalent of 7,000 pixels
Just outside the fovea visual resolution drops to just a few dozen pixels
How often do our eyes move?
3x per second very rapid bro
What are types of modern eye trackers?
Mobile VR
What are Scanpaths?
Fixation - Where our eyes have stopped and focused
and
Saccade - Movements the eye makes
What is a saccade?
An eye movement the eye makes
Rapid, jerky
We cant see while the eye is in motion
The fastest movement the body can make (30-80ms duration)
What can eye tracking tell us?
Distribution of attention
What was noticed
Indicates what is deemed important
Order of importance
How does culture impact how we look at faces?
Western cultures focus on eyes and mouths
East Asian cultures focus on the central area of the face
How does task goal alter scanpaths?
Our cognitive goals
