CogSci 1B Final Exam-Questions with Correct Answers/Verified
Perception I: Visual Perception & Imagery (UNIT) - ✔✔...
When did cognitive scientists start examining the brain during different cognitive processes
and what facilitated this? - ✔✔- 1980s
- functional neuroimaging
Two visual systems hypothesis - ✔✔Two pathways of visual processing
- dorsal stream
- ventral stream
Dorsal stream - ✔✔involved in perception of spatial location
- "where" pathway
- starts in V1 and travels and ends in the posterior parietal cortex
Ventral stream - ✔✔involved in the perception of form
- "what" pathway
- starts in V1 and ends in the inferior temporal cortex
Tri-Level Hypothesis - ✔✔holds that mental or artificial information processing events can
be evaluated on three different levels:
- computational: most abstract (what is the output or purpose?)
- algorithmic: programming level (what steps are being used?)
- implementation: lowest level (what hardware is being used? How are the algorithms
realized physically)
First stage of Marr's Model of Visual Processing - ✔✔when image is projected onto the
retina, it is analyzed in terms of light and dark areas that indicate and determine basic
features of the object such as line segments and shapes. The result is a raw primal sketch of
the image
,Second stage of Marr's Model of Visual Processing - ✔✔When features in the raw primal
sketch are grouped together based on size and orientation to produce a 2.5D sketch that is
viewer-centered
Third stage of Marr's Model of Visual Processing - ✔✔The image is transformed into a 3D
sketch in which axes of symmetry and elongation link the object parts
- sketch is object centered which solves object constancy problem
Symmetry axis - ✔✔line that divides an object into mirror image halves
elongation axis - ✔✔line defining the direction along which the main bulk of a shape is
distributed
Hierarchical Organization of Human Visual System - ✔✔Information flows through a
progression of different areas, each of which generates a representation of increasing
complexity
Human visual system explained - ✔✔1. input from the retina - optic nerve - optic chiasm -
superior colliculus of the brainstem - LGN (in the thalamus)
2. LGN - V1 projects onto the striate cortex
3. V1 - V2
4. V2 - ventral (info goes to V4 then to ITC) or dorsal pathway (info goes to MT then to PPC)
What happens in V1? - ✔✔V1 is retinotopically organized
- neurons/feature detectors perceive low-level features such as orientation and direction of
movement
- also filters info to identify edges and contours
What happens in V2? - ✔✔Neurons here process more complex features of edges, shape,
and depth
,What happens in the inferior temporal cortex (ITC)? - ✔✔specialized areas for face
recognition (fusiform face area) and identification of the human body and body parts
(fusiform body area)
Retinal disparity - ✔✔points on objects located at different distances from the observer will
fall on slightly different locations on the two retinas
- the closer the object, the larger the disparity
- provides basis for depth perception
Extrastriate cortex (secondary visual cortex) - ✔✔processes additional features of visual info
such as movement, spatial frequency, retinal disparity, and color
Trichromatic (three color) theory - ✔✔retina has 3 different cones sensitive to red, green,
and blue wavelengths
- color blind people lack functioning red or green cones
Opponent-process theory - ✔✔the theory that opposing retinal processes (red-green,
yellow-blue, white-black) enable color vision
- they are excited by light in the center and inhibited by light in the surround (e.g some
neurons are turned on by red and turned off by green)
- explains afterimage phenomenon
Which color theory is correct? - ✔✔Both; color processing occurs in 2 stages:
1. retina's red, green, and blue cones respond in varying degrees to different color stimuli
2. then cone's responses are processed by opponent-process cells
Similarities between human visual system & neural networks - ✔✔Information processing is
hierarchically and retinotopically organized
Blindsight - ✔✔a condition where blind people with damage to their visual cortex can guess
the identity or location of particular objects and the particular emotions expressed by faces
in a photo
, Proposed explanation for blindsight - ✔✔there is a second pathway of visual perception
that does not go through the visual cortex, rather it makes a short loop through the limbic
system (emotional/instinctual centers of the brain)
Mental imagery debate - ✔✔is information stored in analog code (pictorial representation)
OR propositional code (descriptive)
Imagery and rotation studies - ✔✔showed there are information processing tasks that take
varying amounts of time even though the quantity of information remains the same
- distinguishes encoding info from how a computer might
- reveals that info may be encoded in pictorial form rather than descriptive
Imagery and size - ✔✔people make faster judgments about the characteristics of large
mental images than of small mental images; also they take longer to travel a large mental
distance
- supports analog mental representation
Imagery and interference - ✔✔Visual imagery may interfere with visual perception, and
motor imagery with motor images
- supports analog mental representation
Imagery and neuroimaging research - ✔✔primary visual cortex and 70-90% of the same
areas during visual perception are activated during mental imagery
- supports analog mental representation
Imagery and parts of figures - ✔✔People have difficulty identifying that a part belongs to a
whole if they have not included the part in their original verbal description of the whole
- Star of David/parallelogram experiment
- supports propositional mental representation
Perception I: Visual Perception & Imagery (UNIT) - ✔✔...
When did cognitive scientists start examining the brain during different cognitive processes
and what facilitated this? - ✔✔- 1980s
- functional neuroimaging
Two visual systems hypothesis - ✔✔Two pathways of visual processing
- dorsal stream
- ventral stream
Dorsal stream - ✔✔involved in perception of spatial location
- "where" pathway
- starts in V1 and travels and ends in the posterior parietal cortex
Ventral stream - ✔✔involved in the perception of form
- "what" pathway
- starts in V1 and ends in the inferior temporal cortex
Tri-Level Hypothesis - ✔✔holds that mental or artificial information processing events can
be evaluated on three different levels:
- computational: most abstract (what is the output or purpose?)
- algorithmic: programming level (what steps are being used?)
- implementation: lowest level (what hardware is being used? How are the algorithms
realized physically)
First stage of Marr's Model of Visual Processing - ✔✔when image is projected onto the
retina, it is analyzed in terms of light and dark areas that indicate and determine basic
features of the object such as line segments and shapes. The result is a raw primal sketch of
the image
,Second stage of Marr's Model of Visual Processing - ✔✔When features in the raw primal
sketch are grouped together based on size and orientation to produce a 2.5D sketch that is
viewer-centered
Third stage of Marr's Model of Visual Processing - ✔✔The image is transformed into a 3D
sketch in which axes of symmetry and elongation link the object parts
- sketch is object centered which solves object constancy problem
Symmetry axis - ✔✔line that divides an object into mirror image halves
elongation axis - ✔✔line defining the direction along which the main bulk of a shape is
distributed
Hierarchical Organization of Human Visual System - ✔✔Information flows through a
progression of different areas, each of which generates a representation of increasing
complexity
Human visual system explained - ✔✔1. input from the retina - optic nerve - optic chiasm -
superior colliculus of the brainstem - LGN (in the thalamus)
2. LGN - V1 projects onto the striate cortex
3. V1 - V2
4. V2 - ventral (info goes to V4 then to ITC) or dorsal pathway (info goes to MT then to PPC)
What happens in V1? - ✔✔V1 is retinotopically organized
- neurons/feature detectors perceive low-level features such as orientation and direction of
movement
- also filters info to identify edges and contours
What happens in V2? - ✔✔Neurons here process more complex features of edges, shape,
and depth
,What happens in the inferior temporal cortex (ITC)? - ✔✔specialized areas for face
recognition (fusiform face area) and identification of the human body and body parts
(fusiform body area)
Retinal disparity - ✔✔points on objects located at different distances from the observer will
fall on slightly different locations on the two retinas
- the closer the object, the larger the disparity
- provides basis for depth perception
Extrastriate cortex (secondary visual cortex) - ✔✔processes additional features of visual info
such as movement, spatial frequency, retinal disparity, and color
Trichromatic (three color) theory - ✔✔retina has 3 different cones sensitive to red, green,
and blue wavelengths
- color blind people lack functioning red or green cones
Opponent-process theory - ✔✔the theory that opposing retinal processes (red-green,
yellow-blue, white-black) enable color vision
- they are excited by light in the center and inhibited by light in the surround (e.g some
neurons are turned on by red and turned off by green)
- explains afterimage phenomenon
Which color theory is correct? - ✔✔Both; color processing occurs in 2 stages:
1. retina's red, green, and blue cones respond in varying degrees to different color stimuli
2. then cone's responses are processed by opponent-process cells
Similarities between human visual system & neural networks - ✔✔Information processing is
hierarchically and retinotopically organized
Blindsight - ✔✔a condition where blind people with damage to their visual cortex can guess
the identity or location of particular objects and the particular emotions expressed by faces
in a photo
, Proposed explanation for blindsight - ✔✔there is a second pathway of visual perception
that does not go through the visual cortex, rather it makes a short loop through the limbic
system (emotional/instinctual centers of the brain)
Mental imagery debate - ✔✔is information stored in analog code (pictorial representation)
OR propositional code (descriptive)
Imagery and rotation studies - ✔✔showed there are information processing tasks that take
varying amounts of time even though the quantity of information remains the same
- distinguishes encoding info from how a computer might
- reveals that info may be encoded in pictorial form rather than descriptive
Imagery and size - ✔✔people make faster judgments about the characteristics of large
mental images than of small mental images; also they take longer to travel a large mental
distance
- supports analog mental representation
Imagery and interference - ✔✔Visual imagery may interfere with visual perception, and
motor imagery with motor images
- supports analog mental representation
Imagery and neuroimaging research - ✔✔primary visual cortex and 70-90% of the same
areas during visual perception are activated during mental imagery
- supports analog mental representation
Imagery and parts of figures - ✔✔People have difficulty identifying that a part belongs to a
whole if they have not included the part in their original verbal description of the whole
- Star of David/parallelogram experiment
- supports propositional mental representation
