Unit 4- Senses and Perception Flashcards
sensation
sensory receptors receive/represent stimulus energies from env.
perception
organizing/interpreting sensory info, recognize meaningful objects/events
bottom-up processing
sensory receptors -> higher level processing (assembling and integrating information) (What am I seeing?)
top-down processing
construct perceptions from experience and expectations (Is that something I’ve seen before?) (Brain can start to see things when given hints at what they are looking at)
selective attention
focusing conscious on particular stimulus
inattentional blindness
cant see visible objects when attention directed elsewhere
change blindeness
fail to notice changes in environment
transduction
converting one form of energy into another
psychophysics
study of relationship between physical characteristics of stimuli vs psychological experience on them
absolute threshold
minimum stimulation needed to detect stimulus 50% of the time (candle viewed from 30 miles away on clear night, 1 tsp of sugar dissolved in 2 gallons of water)
signal detection theory
predicting how/when we detect presence of faint stimulus and background stimulation
sublimal
below one’s absolute threshold for conscious awareness
priming
activation of certain associations, often unconscious
difference threshold
minimum difference between 2 stimuli required for detection 50% of the time (The smallest amount by which two stimuli can differ in order for an individual to perceive them as different.)
Weber’s Law
to be perceived as different, 2 stimuli must differ by a constant minimum percentage (not constant amount)
sensory adaptation
diminished sensitivity as consequence of constant stimulation
perceptual set
mental predisposition to perceive one thing and not another, what we expect to see, which influences what we do see (old lady or young woman picture, bunny or duck picture) (top-down processing) (flying saucers or clouds?)
extrasensory perception (ESP)
claim that perception can occur apart from sensory input (telepathy, psychics)
parapsychology
study of paranormal phenomena (ESP/telekinesis)
wavelength
distance from peak of one light/sound wave to peak of next (short wavelength=high frequency, determines color/hue of waves)
hue
color determined by wavelength of light
intensity
amount of energy in light/sound wave, perceive as brightness/loudness, determined by wave’s amplitude (height), bright or dull colors
pupil
center of eye, light enters
iris
colored portion “ring” of eye, controls size of pupil opening
lens
transparent, behind pupil, changes shape to help focus images on retina
retina
light-sensitive inner surface of eye, receptor rods/cones, neurons processing visual info
accomodation
eye’s lens change shape to focus near or far objects on retina
rods
retinal receptors, detect black/white/grey, necessary for peripheral/night vision when cones don’t respond
cones
retinal receptor cells, center of retina, function in well-lit conditions, detect fine detail and give rise to color sensations
optic nerve
carries neural impulses from eye to brain
blind spot
point where optic nerve leaves eye, creating blind spot because no receptor cells there
fovea
central focal point in retina, eye’s cones cluster
feature detectors
nerve cells in brain that respond to specific features of stimulus (shape/angle/movement)
parallel processing
processing many aspects of a problem simultaneously
Young-Helmholtz trichromatic (three-color) theory
theory that retina contains 3 different color receptors (sensitive to red, blue, and green), when stimulated in combination, can produce perception of any color
opponent-process theory
opposing retinal processes (red-green, yellow-blue, white-black) enable color vision
gestalt
organized whole (integrate pieces of info into meaningful wholes)
figure-ground
organization of visual field into objects that stand out from surroundings (some artists give us two equal choices about what is figure ground using negative and non-negative space, goblet or two faces)
grouping
perceptual tendency, organize stimuli into groups
depth perception
ability to see 3D objects although images that strike retina are 2D, judge distance
visual cliff
lab device for testing depth perception in infants/young animals
binocular cues
depth cues that depend on use of 2 eyes
retinal disparity
difference between 2 images, retinas receive slightly different images, greater distance, closer object
monocular cues
depth cues, available to either eye alone
phi phenomenon
illusion movement, lights blink on and off in quick succession
perceptual constancy
perceiving objects as unchanging even as illumination/retinal images change
color constancy
perceiving familiar objects as having constant color, even if changing illumination alters wavelengths reflected by the object
perceptual adaptation
ability to adjust an artificially displaced/inverted visual field, in vision
audition
sense/act of hearing
frequency
number of wavelengths that pass point in given time
pitch
tone’s highness/lowness
middle ear
3 tiny bones, between eardum and cochlea (hammer, stirrup, anvil), concentrate vibrations of eardrum on cochlea’s oval window
cochlea
coiled/bony/fluid-filled tube in inner ear, sound waves traveling through cochlear fluid trigger nerve impulses
inner ear
innermost part of ear, waves of fluid move from oval window to cochlea’s “hair” receptor cells. These cells send signals through auditory nerves to temporal lobes.
sensorineural hearing loss
damage to cochlea’s receptor cells or to auditory nerves (nerve deafness)
conduction hearing loss
damage to mech. system that conducts sound waves to cochlea
cochlear implant
device, convert sounds to electrical signals/stimulating auditory nerve
place theory
theory, links pitch we hear with place where cochlea membrane stimulated
frequency theory
theory, rate of nerve impulses traveling up auditory nerve matches frequency of tone, enabling us to sense pitch, at low sound frequencies, hair
cells send signals at whatever
rate the sound is received
gate-control theory
theory, spinal cord contains neurological gate that blocks pain signals/allows them to pass on to brain, opened by activity of pain signals
kinesthesia
system for sensing position/movement of individual body parts
vestibular sense
sense of body movement/position, including sense of balance
sensory interaction
one sense influences another
embodied cognition
influence of bodily sensations/gestures/cognitive preferences and judgements (if you feel socially excluded, you will feel colder) (if someone uses left hand on mouse, more likely to lean left)
Gustav Fechner
absolute thresholds/studied awareness of faint stimuli, psychophysics founder
Ernst Weber
Weber’s Law
David Hubel
feature detectors, brain cells convey info to enable us to see world
Torsten Wiesal
feature detectors, visual development, visual processing by cerebral cortex
How light from candle passes through eye
Goes through cornea and pupil, then gets focused on lens and inverted by lens. Light lands on retina, where it does transduction into neural impulses to be sent out through optic nerves
Additive color mixing
Add all light wave colors together, get white
Subtractive color mixing
Mix all paint colors together, get black
3 ways of grouping: how we make gestalts
proximity, continuity, and closure
interposition
monocular cue, a visual signal that an object is closer than the ones behind it because the closer object covers part of the farther object.
relative size
monocular cue, we intuitively know to interpret familiar objects (of known size) as farther away when they appear smaller
linear perspective
a visual cue in which two parallel lines appear to meet together in the distance
relative motion
monocular cue, when we are moving, we can tell which objects are farther away because it takes longer to pass them
shading effects
monocular cue, helps our perception of depth (does the middle circle bulge out or in?)
outer ear
collects sound and funnels it to eardrum
hearing loss
damaged hair cells in ears and damaged inner ears, limit sounds over 85 decibels and treat ear infections to prevent hearing loss
volley principle
at ultra high frequencies, receptor cells fire in succession, combing signals to reach higher firing rates
synesthesia
condition when perception in one sense is triggered by a sensation in a different sense (rock music seems purple, the number 7 gives me a salty taste)
