mod 18 - vision and perceptual organization and interpretation Flashcards
Wavelength
distance w/i a light wave from one peak to another (color)
amplitude
distance on y axis from peak to trough (brightness)
Define accomodation
The process of the eye lense changing its shape on the retina to focus on different distanced objects
AP TERM: Acuity
visual acuity = sharpness of vision as impacted by eye shape distortions (20/20 vs. literally you)
rods vs cones (and how many of each in an eye?)
120 million rods, 6 million cones
Rods see black and white and grey in your periphery)(also happen to be located in the peripheral retina) with a high sensitivity to light in dim conditions (grey has the most shades)
cones see color near the center of the retina, with fine-detail and well-lit conditions
(CCC - Cones, color, center)
Blind spot
area where there are no receptor cells, thus no vision (where the “stem” connects to the eye)
Feature detectors
nerve cells in brain whcih respond to different angles of lines, shapes, angles, and movements (a desk vs. eshan tanseer)
Parallel Processing
Processnig multiple things simultaneously (bird outline, color, depth (the wings are closer than the face) and motion = bird)
trichromatic color theory/young and helmholtz
3 retina color receptors, red, green, blue
NOT RGB THEORAY
Opponent-Process Theory
Opposing retinal processes allow for color vision. you look at green, thus the retina and thalamus green-sensitive neurons fire. this means that when you look back, the neurons are more tired than the red-sensitive ones, so they are overpowered.
(ex. stare at green for a while, look away you see red)
Opponent pairs:
red-green
blue-yellow
white-black
Stages of color processing
- Red, green, and blue cones respond to color stimuli to different extents
- opponent-processing cells process signals before they reach visual cortex
Color constancy
familiar objects are PERCEIVED as constant color despite changing light levels altering wavelength of light from object
COMPARISONS GOVERN OUR PERCEPTIONS
does every organism see the same colors we do
nah
What is ESP? what researches claims of it?
Extrasensory perception (ghosts, auras of ppl, stuff like that)
the field of Parapsychology
blindsight
cant see something, but cisual cortex provides instinct of such that you can guess the position without even seeing it perfectly
aspects of parallel processing/supercell processing
color, movement, form, and depth
afterimage
look at something for a while, look at something else, and you see the opposite of the color you were originally looking at
can you detect red and green from the same place at once?
no, they are opponent colors. when greeen receptors are turned on, red are turned off, and vise versa,
how does your brain recognize a face?
retina information —> mutliple visual cortex areas and compared to stored info
two key theories of color vision?
- trichromatic theory
- opponent-process theory
both compliment each other, trichromatic says we see in red green blue and opponent process says we see those red OR green, blue OR yellow, and black OR white from single point
define gestalt in the context of psychology
gestalt = organized whole, in thsi case the integrated pieces of information received from superclusters that we process and make into a whole and embue with meaning
elements/types of grouping:
proximity (think two lines closer together are turned into a set rather than just two lines)
continuity from possible discontinuous patterns (curves with a line cutting off both halves)
closure: necker cube, fill in gaps
binocular cues
depth cues that depend on both eyes (the stuff that lacks, thus difficulty in perceiving depth with one eye)
- retinal disparity (less = further, more = closer) (only with short-distances though)
can you have depth perception with one eye?
yes, just more difficutly in doing so
