Object Recognition and Attention Flashcards
In what region of the brain is the What vs Where pathways?
What pathway - ventral stream in inferior temporal cortex
Where pathway - dorsal stream in posterior parietal cortex
What experiment is associated with the what vs where pathways?
Tested people with lesions in the dorsal or ventral pathway.
What deficit: Visual form agnosia
Could: draw pictures from memory
Could not: recognize or copy pictures, recognize own drawings
Could: Place card in slot
Could not: Report orientation of slot
Could: Make hand gestures
Could not: Describe function of objects (think of video of guy who couldn’t remember a lock)
Where deficit: Optic ataxia - didnt know where objects were in space but they could recognize what they were
Task 1: WHAT
Object Discrimination - Is this cylinder and rectangular prism identical?
Task 2: WHERE
Landmark Discrimination - Reach out and grab this item
Is activity linked to awareness of conscious experience or to raw stimuli (regardless of awareness)? Think of experiment where they show people a house and a face at the same time. Which do they perceive?
Activity Tracks Awareness
They go back and forth between seeing a house and seeing a face. FFA lights up only when you see the house (only when you think you are seeing a face vs actually seeing a face)
The visual system uses what to simplify & aid visual processing?
rules, heuristics, and tricks
What assumption was false regarding the Ames room?
That the corners meet at 90 degrees
What is Gestalt Psychology? What are the Gestalt principles?
The sum equals more than the parts
‘emergent features’
Proximity, Similarity, Connectedness, Common fate, Good continuation, closure
What are ways to resolve ambiguity?
Figure/ Ground
Using Context
Non-Accidental properties
geons are viewpoint independent (non-accidental properties). What are examples of non-accidental properties?
Co-linearity, Curvilinearity, Cotermination, Convergence, Parallelism, Equal Spacing
Which of the following is supportive of the claim that perception is in the eye of the beholder and not in the stimulus itself?
A. When presented with ambiguous letters, the visual system uses context to determine their identity
B. a traffic light can be identified even if partially occluded by a tree branch
all of the above
Which of the following is evidence for a feature theory of perception?
The visual system is specialized with cells that detect single features
When betty is shown strings of letters tachistoscopically, they are overregularized to follow the rules of common English spelling. This is because
of a lifetime of strengthening the bigram detectors for common English letter pairs
McClelland and Rumelhar’s model of a feature net makes use of all of the following statements EXCEPT:
the elimination of feature detectors, relying instead on geon detectors
We can often recognize an object even if some of the object’s parts are hidden from view. Evidence indicates that this recognition from partial viewing will be easiest if:
we can see enough of the object to identify some of its geons
In the visual search paradigm, which of the following takes the LONGEST? finding a RED CIRCLE in a field of
10 green circles and 10 red squares
visual agnosia is
deficit in object recognition with a preserved ability to use visual information to guide action
Which of the following statements applies to stimulus-based priming but NOT to expectation-based priming?
It is bottom-up
You are at a cocktail party conversing with a friend. In this situation, you are MOST likely to hear
that you name is being called out by the person next to you
In the absence of attention:
stimuli may not be consciously perceived but can still have an influence on the perceiver
in a feature net model, knowledge of spelling patterns
is distributed across the model, and therefore the knowledge is only detectable in the overall functioning of the network
Moore and egeth showed participants a display containing 2 horizontal lines and a series of surrounding dots. In this experiment most participants were
not consciously aware of the patterns and perceived the 2 lines to be of different lengths
A participant is shown a series of stimuli and is asked to name the color of the ink in which the stimuli are printed. The 8th stimulus happens to be printed in green ink. We should expect a relatively slow response if the stimulus happens to be
the word RED printed in green