Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
72 Cards in this Set
- Front
- Back
|
What are the different types of testing for visual acuity? |
Grating acuity (Smallest lines) Snellen acuity (Smallest letter) |
|
|
At birth, what is the average human's acuity? at 20? |
20/600, 20/20 |
|
|
What are the dimensions of patterns? |
Spatial frequency, orientation, phase and contrast |
|
|
What is Gestalt psychology? |
It is a theory of mind that tries to understand how we acquire and maintain meaningful perceptions in an otherwise chaotic world. Adheres to the principle "the whole is different from the sum of its parts" |
|
|
What is bottom up perceptual processing? |
build up from physical properties |
|
|
What is top down perceptual processing? |
knowledge and thought that organizes perceptual world. |
|
|
What is figure-ground segregation? |
A type of perceptual grouping vital for perceiving objects whereby one is able to distinguish a distinct and sharply defined shape or figure from the remainder of the visual field or ground |
|
|
Who is associated with the quote "The whole is other than the sum of its parts" |
Wertheimer |
|
|
what did wertheimer propose? |
innate organizing structures |
|
|
What was the gestalt principles and what do they mean? |
Law of proximity-objects close to one another tend to group as a unit law of similarity-similar objects tend to group law of uniform connectedness-elements that appear physically connected group law of good continuation- elements tend to be groups to produce simplest structure law of common fate- elements that move together are grouped law of symmetry-symmetrical elements group together law of closure-incomplete contours tend to be bounded as a unit
|
|
|
What does the law of pragnanz mean? and what is it? |
Means law of good figure and says we perceive the most simple and stable figure
|
|
|
What is figural goodness? says your teacher |
inversely proportional to information needed to specify a figure |
|
|
What did Newton's experiment reveal? |
White light contains all colors |
|
|
What is the basis of color in objects? |
differential absorption and reflection |
|
|
what does the color red absorb and reflect |
red absorbs all but red wavelengths and reflects only red wavelengths |
|
|
What are the attributes of color? and what are they? |
Hue: color Saturation: relative amount of color; how pure it is and how much white it contains |
|
|
What are additive color mixtures and give some examples? |
lights, tv, computer. Additive color mixtures are colors made by lights and reflect only their wavelengths and when added to another color with opposing wavelengths could be nullified, as in the case with yellow and blue |
|
|
what are subtractive collor mixtures and what are some examples? |
paint, dye. pigments that absorb some wavelengths and reflect all others and when colors are added, wavelengths that are reflected are subtracted. |
|
|
What is Young-Helmholtz trichromatic theory? |
assumes that there are 3 kinds of receptors with distinct spectral sensitivity functions for each receptor |
|
|
What is the receptors' absorption property? |
measured absorption of cones for different wavelengths |
|
|
What is the receptors' electrophysiological property? |
measured response amplitude of cones for different wavelengths of light |
|
|
What is Hering's opponent process theory? |
the three types of cones (short, medium and long) responsible for receiving sensory input compose opponent processes and channels which help the brain to sort out colors as some absorb the same wavelengths as others, so they take into account differences in absorption. opposing colors are blue-yellow, red-green and black-white. They are more central in nervous system than receptors. |
|
|
How do we measure the opponent process? |
Hue canellation method: monochromatic stimulus (one wavelength), add in opposing color until there is no noticeable color with the result of appearing gray. |
|
|
What happens in the two stage theory of color? |
small cones excite blue-inhibit yellow, medium cones excite green and yellow-inhibit red and blue, long cones excite yellow and red-inhibit blue and green |
|
|
What are the classes of depth cues? |
monocular and binocular |
|
|
what are the two monocular cues |
pictorial: information available from stationary inspection of a scene and kinetic: information available from movement |
|
|
What are the different depth cues? |
Size, relative size, familiar size, interposition (occlusion), height (more distant objects are closer to the horizon [below horizon, distant objects appear higher, above horizon, distant objects are lower]), linear perspective (near portions appear smaller of receding objects [road]) |
|
|
Who came up with the geological approach to depth perception? |
J.J. Gibson |
|
|
What does the Geological approach to depth perception emphasize? |
constant or invariant information in the visual world: texture gradients are a perceptual invariant |
|
|
what is a kinetic depth cue and what are the rules for it? |
motion parallax- close objects move more rapidly, objects closer than fixation point move in opposite direction, objects farther than fixation point move in the same direction |
|
|
What is convergence? |
the inward movement of the eyes when looking at a close image |
|
|
what is binocular disparity? |
difference between two retinal images of an object, this DECREASES WITH DISTANCE OF OBJECT!! |
|
|
characteristics of the binocular depth cells in the cortex? |
respond when different positions on two retinas are stimulated, tuned to selective disparities |
|
|
What was the Gibson and Walk experiment? |
created the illusion of a drop and had children play in room, 2 month olds attend (HR decel) to deep side, 6-14 month olds fear (HR accel) to deep side
EXPERIENCE IS IMPORTANT |
|
|
What is the development of convergence? |
birth -1 month minimal convergence 2 months- some convergence reliable convergence by 3 months RECALIBRATION NECESSARY DURING 1ST YEAR
|
|
|
Development of binocular disparity |
no detection before 3 months dramatic improvement between 14 and 18 weeks develop stereopsis (impression of depth resulting from binocular disparity)
|
|
|
Sound (physical stimulus) |
fluctuations in pressure due to object's vibration |
|
|
What is compression? |
when molecules draw together |
|
|
What is rarefaction? |
When molecules draw apart |
|
|
What is frequency? how is it measured? what frequencies can we hear? |
# of cycles per second, measured in Hertz, we can hear frequencies between 20 and 20000 hertz |
|
|
What is the amplitude of a sound wave? how is it measured? |
maximum change from normal air pressure (measurement from bottom of wave to top of wave), sound pressure level, measured in decibels |
|
|
What is a phase? |
specific point in cycle reached at a certain point in time, 1 cycle is 360 degrees |
|
|
what are sound's subjective attributes? |
pitch-related to frequency, provides melody loudness-related to amplitude timbre-related to frequencies and phase relations, quality of instruments |
|
|
What is the pinna? |
funnels and filters sound waves |
|
|
where is the tympanic membrane? |
middle ear |
|
|
What are the middle ear's ossicles? |
malleus, incus, stapes |
|
|
where is the oval window? |
the inner ear |
|
|
what parts make up the cochlea? |
basilar membrane, auditory hair cells (stereocilia)
|
|
|
characteristics of a traveling wave on the basilar membrane |
narrow and rigid at base, wide and loose at apex |
|
|
What is a component of Von Beksy's tonotopic coding? |
the peak of a traveling wave varies with frequency |
|
|
what is the modern place theory? |
high frequencies displace basilar membrane in base of cochlea, low frequencies displace basilar membrane in apex of cochlea |
|
|
what is the organ of corti? |
on the bottom of the cochlear duct |
|
|
how many rows of hair cells are on the inner row/rows? outer? |
one, three or four |
|
|
What happens in transduction? |
basilar membrane movement bends hair cells, this opens receptors to potassium ions which elicits generator potential |
|
|
what are auditory nerve fibers? what do they do? |
tuned neurons, respond best to one characteristic frequency |
|
|
what is tonotopic coding and where is it present in the auditory system? |
cells lying close to one another responding to similar frequencies at all levels of the auditory system |
|
|
How are frequency-tuned cells arranged in the auditory cortex? in what fashion? |
in columns, perpendicular |
|
|
What is place theory? |
the peak of the wave on the basilar membrane varies with frequency, different hair cells respond to different frequencies, nerve fibers are tuned by frequency, cells in pathway are tuned by frequency |
|
|
selective threshhold increases after exposure to how many hz |
4000 |
|
|
temporal periodicity theory |
nerve fibers fire once per cycle for low frequencies, under 1000hz |
|
|
place vs periodicity theories |
place: identifying the cell that fires gives the frequency or pitch of the sound periodicity: monitoring the rate of firing gives period of sound and its frequency or pitch |
|
|
What is the Volley principle? |
at high frequencies multiple nerve fibers combine |
|
|
three binaural processing jobs |
picking signal out of noise, segregating sound streams, auditory localization |
|
|
What is azimuth |
horizontal direction of sound |
|
|
what is elevation |
vertical direction of sound |
|
|
what is interaural time difference |
difference in time of arrival of sound at two difference ears, usually 10-20 microseconds, but varies with location of stimulus best at low frequencies |
|
|
what is interaural intensity difference |
change in intensity between the two ears ie: sound energy is more intense at the nearer ear=duh best at high frequencies |
|
|
what is the problem with the dual-process theory? |
does not deal with reverberant environments |
|
|
what is precedence effect? |
leading inpute determines perceived location of a sound holds for delays up to 10-14 ms |
|
|
Where are ITD and IID sensitive cells found? |
inferior colliculus, medial geniculate, auditory complex |
|
|
What does a lesion of the superior olive destroy? |
localization |
|
|
what does a lesion of the inferior colliculus damage? |
localization ability |
