Chapter 4 Flashcards
(47 cards)
how do we recognize spots?
retinal ganglion cells + LGN
how do we recognize bars
PVC = v1 = STRIATE CORTEX
_______: the region of cortex bordering the primary visual cortex
extrastriate cortex
where pathway is temporal or parietal love
parietal
after the extra striate cortex is what?
processing of info into the the “ what pathways” the where pathways dorsal pathway
V1 goes to V2 first or higher order areas first?
higher order areas
texture is a way of grouping
dont worry about deep learning models !
the monkey visual system is an example of feedforward or feedbackword
feedforward
the receptive fields of extrastriate cortex are more _____ than those in the striate cortex ?
more sophisticated
extrastriate cortex respond to ______ and is important for _______
visual properties
perceiving objects
ex) boundary ownership
explain boundary ownership
the striate cortex (V1, Primary visual cortex) can see that there is a line there and there are two colours but the extrastriate cortex is able to see the larger image like yes there are multiple lines here that depict that those lines are owned by this black box in a white background. the striate cortex is unable to do so it can only tell that there is a side of black and white cant see the full picture.
______ part of the cerebral cortex in the lower portion of the temporal lobe, important for object recognition
- part of the “what” pathway
IT cortex:
Inferotemporal cortex
when IT cortex is lesioned, it leads to ______?
agnosias: failure to recognize objects in-spite of the ability to see them
ex) somoeone says
“pick up that clock” they pick it up
then someones says “what is this?” (pointing at the clock) they cant recognize it
Inferotemporal cortex (IT) receptive field properties
- very large
- do not respond well to spots or lines
- respond well to stimuli such as hands, faces, or objects
explain the Grandmother cell/ Jennifer Aniston cell
when testing if a cell responds specifically to Jennifer Aniston
they found a cells response fired most when seeing her and other things little to no activity
object recognition is _____ and happens in ________
fast
150ms
explain the reverse-hierarchy theory
Hoch & Ahi Proposed:
- feed-forward to higher levels of the brain give initial curde info
- more detailed info comes available when they activate the lower visual areas
_______: loosely defined stage of visual processing that comes after BASIC FEATURES HAVE BEEN EXTRACTED FROM THE IMAGE and BEFORE object recognition and scene understanding
mid-level vision
mid- level vision involves what?
- perceptions of edges + surfaces
- determines which regions of an image are/ aren’t grouped together
true or false computer-based edge detectors are not as good as humans?
true sometimes they don’t find edges as easily as humans do
ex) gradient on gradient. at one point in time both gradient colours match causing computer to believe there is no line but our brains just automatically show us there is a line there even though colours are the same and there shouldn’t be a line/ difference in that area
when we see an object (arrow) which has a gradient pattern of colour on top of a gradient background and a computer cannot see the segments that match the gradient colour but we can. what is this called?
illusory contour: a contour that is perceived even though nothing changes from one side of the contour to the other
_____ can cause us to see one thing two ways one is more dominant but we can see both if told the other option
illusory contours
explain Gestalt psychology
“the whole is greater than the sum of its part’s”
explain Gestalt grouping rules:
set of rules that describe when elements in an image will appear to group together
similarity: similar items tend to group tog
proximity: items that are near tend to group tog
