Chapter 5: Sensation and Perception Flashcards
sensation (biological)
detction of physical energy by orur semse organs that send info to brain
transduction
nervous system converts stimulus into electrical signals in neurons
absolute threhsold
lowest level of a stimulus that we can detect 50% of the time
- ex: can see a candle from 30 miles away on a clear night
subliminal messages
presented below threshold for conscious awareness
noticeable difference (difference threshold)
how much change in a stimuli is required for us to notice the change between them
-chnages based on stimulus intensity
- ex: phone light in dark movie
webers law
the stronger tthe stimulus, tje greater chnage neccesary to detect a difference
ex: adding 1 lb to 5 lbs vs adding 1 lb to 50 lbs
perception (cognitive)
sensory info organuzed, interptewted, consciously experienced
bottom up processing
perceiving items w/ sensation as opposed to our concepual ideas (starts w/ simplest level)
top down processing
cocneptually driven; infuenced by beliefs and expectancies
ex: lump in road is clothes not dead animal
sensory adaptation
often ddont percieve stimuli that remain relatively constant over prolonged periods of time
ex: other peoples houses smell weird but ours doesnt
inattentional blindness
failure to detect something obvious while paying attention to something else
signal detecttion theory
ability to detect stimulus when its embedded in a distracting background
- ex: seeing friend in sea of faces
ppl from the __ cultures are more prone to certain types of visual illusions than ppl from __ countries (and vice versa)
western cultures; non-western
ex: ppl in western cultures have a perceptual context of buildings w/ straight lines while ppl from other countries see right through this illusion
amplitude
distance from center line (either to top/bottom)
wavelength
lenght of wave form peak to peak
frequency
of waves that pass a given point in a given time period
hertz
cycles per second
longer wavelengths =
lower frequencies
shorter wavelengths =
higher frequencies
visible spectrum
part of larger elecgromagnetic spectrum that we can see
electromagnetic spectrum
all electromagnetic radiation that occurs in our environment
ex: gamma rays, x-rays, uv light, etc…
in vision, red is associated w/
longer wavelengths
in vision, blue/purple is associated w/
shorter wavelengths
larger amplitude of light waves =
brighter color
pitch
frequency of sound waves
- high: high pitch sound
- low: low pitch sound
decibels
height of sound waves; our experience of loudness
- hearing damage: 80-13- dB
timbre
quality of sound wave
- combo of frequency, amplitude, and timing of sound waves
cornea
transparent covering over eye
- focus light waves inside of eye
pupil
small opening in eye through which light passes (see chnages w/ light levels + emotional arousal)
- low light: pupil dilates (more light)
- high light: pupil constricts (less light)
iris
eye color
lens
curved, transparent structure that provides additional focus
- can change shape to focus light (we can feel this change)
fovea
lens focus images perfectly on this small indentation in back of eye
retina
light sensitive lining of eye
cones
color vision; acute detailsl spatial relation
rods
long/narrow; helps see basic shapes/forms
dark adaptation
time for rods to adjust to greater sensitivity
optic nerve
rods and cones are connected to retinal ganglion cells
axons from retinal ganglion cells….
converge/exit the back of eye to form optic nerve,
optic nerve carries what?
visual info from retina to brain
blind spot
where optic nerve exits the retina
- not consciously aware of this
1. each eye has slightly diff view
2. visual system fills in blind spot for us
optic chiasm
where optic nerve from eahc eye merges just below brain
- info from right left visual field goes to left hemisphere and vice versa
trichromatic theory of color vision + has what 2 theories that aren’t mutally exclusive?
all colors come from primary colors (red, blue, green)
oppenent process theory/trichromatic theory of color vision (apply to diff levels of bervous system)
- trichromatic: cones repsond to diff wavelengths that represent red, blue, green
-opponent: signal moves past retina and cells respond in a consistent way to opp-pro theory
oppenent process theor
color is coded in opponent pairs: one cell is excited by one of the opponent colors and inhibited by the other
- black/white
- yellow/blue
- green/RED
after image
continuation of visual sensation after removal of stimulus
depth perception
abilitu to judge distance of objects/spatial relation of objects at diff distances
binocular cues
uses both eyes
- bi = 2
- ocular = eyes
binocular disparity
slightly diff views of world each of our eyes receive
monocular cues
one eye
- mono = 1
- ocular = eye
linear perspective
perceive depth when we see 2 parallel lives that seem to converge in an image (ex: highway merges into only 1 lane)
parts of outer ear:
pinna (visible); auditory canal; tympanic membrane (eardrum)
ossicles
names the malleus (hammer); incus (anvil); stapes (stirrup)
inner ear parts:
semi-circular canals (balance and movement)(vestibular sense); and cochlea (fluid-filled, snail shaped structure that contains sensory receptors) (aka hair cells)
sound waves hit __ then __ then __ then __
auditory canal + strike tympanic membrane; then moves the ossicles, then stapes presses into cochlea (oval window); then hair cells are stimulated in the basilar membrane
basilar membrane
thin strip of tissue w/in cochlea
temporal (frequency) theory of pitch perception
frequency is coded by activity level of sensory neuron
place theory of pitch perception
diff portions of the basilar membrane are sensitive to sounds of diff frequencies
- base respodns better to high frequencies
- tip responds better to low frequencies
monaural cues
one ear; each pinna interacts w/ incoming soudn waves diff depending on sounds source relative to our bodies
binaural cues
two ears; sounds will arrive at one ear slightly before the other ear
gustation
taste (sweet, salty, sour)
umami
japanese word that means pleasant-savory taste
- associated w/ glutamates and nucleotides (meats, fermented foods, mushrooms)
olfaction means
smell
olfactory receptors
cells located in mucous membrane at top of nose
- hairlike extensions are receoptirs for sites for color molecules
olfactory bulb
tip of frontal lobe where olfactory nerves begin
- works w/ gustation to produce flavor
- infor sent to regions of limbic system/primary olfactory bulb
gestalt psych
breaking psych phenomena down into small parts would not lead to undertstaning psych
- best way to view phenomena is as organized structural wholes
gestalt principles
rules governing how we perceive objects as wholes w/in context
figure-ground relationship
decision about what is foreground/what is background
proximity
objects physiclaly close to each other seen as unified wholes
similarity
we see similar objects as comprising a whole
continuity (good continuation)
lines are seen as following the smoothest path
closure
we fill in what is missing in partial info
