Perception and Sensation Flashcards
stimulus
outside factor affects senses
receptor cells
specified neurons receives message and send to brain
detection
awareness of a stimuli
discrimination
telling 2 stimuli apart
noise
not just what you hear background stimuli ex. heat disco taste in mouth lights peripheral vision microphone
Psychophysics
human factors study physical energy and psych experience why did you respond to that how colors affect mood ideal brightness for dashboard lights
Gustav Fechner
psychophysics experimental thought sensation couldn't be measured, only compared linked physical to subjective measured maxes and mins
absolute threshold
how faint a stimuli can be and still be detected 50% of the time
when can a candle be seen in the distance
difference threshold
just noticeable difference
min difference needed to tell 2 stimuli apart
when can the difference in brightness be detected in a candle in the distance
when is something louder
tone demo
Weber’s law
blindfold shoe quarter demo proportional percent difference to sense it weight 2% jnd touch 4% jnd saltiness 20% jnd
signal detection theory
box with whether a stimuli was present/ whether it was setected
hit
a stimuli was present and detected
part of signal detection theory
hear baby cry and go to it
miss
signal present but not detected
part of signal detection theory
don’t hear baby cry
false alarm
signal absent but person says they detect the stimulus
part of signal detection theory
think you hear baby cry but nothing there
correct rejection
signal absent and person says that they do not detect it
part of signal detection theory
knowing that the person who thought the baby was crying when it wasn’t was wrong because you didn’t hear it
Detecting a stimulus
all senses do this
distal stimulus
the actual object event sound or smell
ec. bush in courtyard
all sense have this
transduction
changing stimulus into a electrochemical message
all sense do this
receptor cells transduce the image
proximal stimulus
the stimulus as an electrochemical message
the bush on retina (would be upside down)
intensity
amount of stimulus
measured in neurons
part of all senses
quantitative info
rate of neural firing
part of all sense
qualititative info
which neurons are firing? different receptors firing different combinations part of all senses eye red cones and green cones sweet and sour receptors
sensory adaptation
decline in receptor activity when stimulus is unchanging
habituation
decline in receptor activity when stimulus is unchanging
getting used to it
ex. swimming a cold pool
takes place in brain
sensory restriction
limit stimuli
healthy when you choose it
unhealthy when you don’t choose it (torture) (sensory deprivation)
Divided Attention
focusing on two things
ex. reading and watching tv
phone and studying
Selective Attention
Choosing which stimuli to pay attention to
ex. watching tv parent calls
Cocktail party effect
when attention shifts automatically from one person to someone else
convo with someone, hear name or something that grans attention
Change Blindness
Video with consent experiment and t shirts
miss large changes in visual world
someone else’s problem
Dichotic Presentation
attention test
two stimuli people asked to attend to one or both
moonwalking bear
dichotic listening
two stories
dichotic viewing
moonwalking bear
Subliminal Perception
idea- a stimulus can affect a person’s behavior even if not consciously processed
ex. Movie previews “eat popcorn” flashed
does not necessarily change behavior
no difference with popcorn
studies indicate not true
priming
different than subliminal messaging-- priming is for a word, not a behavior short term effect for priming pick it up and apply it flash "pencil" associated word with pencil
receptors in the eye
photoreceptors
RODS AND CONES
message transmission in eye
stimulus (light) hits photoreceptors—> transduce light waves into electrochemical messages so nervous system can process it (rods and cones —> bipolar cells —> ganglion cells)
the axons of these ganglion cells make up the optic nerve, which joins each eye at brain base
optic nerve —-> thalamus —-> occipital lobe —> visual cortex —-> specialized cells which fire for particular features (motion and feature detector cells )
motion detector cells
detected motion
feature detector cells
help you read
features put together in brain
look at aspects of letters and stuff
stimulus in vision
light #prism #Newton
True or false: most objects emit light
false, most reflect it
Brightness
= intensity [depends on how it hits the retina and the environment]
one of the very important properties of light
Color
very important property of light
determined by hue and saturation
hue
like shades
roughly 150 total hues
our perception of color doesn’t always match spectrum
saturation
measure of hue’s vividness
(purity)
“true” color [not too much white or black]
primary colors of pigment
art class
pigment absorbs light
also called primary subtractive colors
red + blue + yellow= black
primary colors of light
theater
stage lighting
additive primary colors physics
red + yellow + blue = white
Color Vision
over 150 million colors
Trichromatic Theory (Young-Helmholtz theory)
3 types of color receptors (cones)
red, green , and blue
red- red and yellow (long waves)
green- green, less yellow (medium waves)
blue- blue (short waves)
combine in different ways
sensitive to WHOLE spectrum, but in particular to part
fire more frequently certain colors
overlap and combine
test- colorblindness test (defective cones)
Opponent-process theory
more in ganglion cells after receptors receive message (ganglion cells) 2 sets of opponent colors blue/yellow and red/green responsible for hues cells get excited/inhibited. When one gets excited (like blue) another (yellow) gets inhibited test/evidence: afterimage test
light adaptation
squint
pupils constrict
iris contracting over pupil
dark adaptation
adjust to dark light
30 min
iris expands to let more light into pupil
Nearsightedness
myopia
eyeball too long
incoming light waves focus in front of retina, which blurs far away objects
Farsightedness
hyperopia
eyeball too short waves focus behind retina, blurring nearby objects
cataracts
lenses become cloudy are removed or lzaers
often with diabetes old age as well
Glaucoma
excess fluid (blood) behind eye and receptors can't fire pot helps it (marijuana is a vasoconstrictor)
Blindness
damage to eye (most common)
damage to nerves (addicent)
damage to visual cortex
stimulus in hearing
vibration in ear
Loudness
determined by amplitude or strength of sound wave
Pitch
frequency determines pitch
frequency determined by wave length
greater wave length, lower pitch
decibels
measuring unit for sound
middle ear
energy [0 is abs threshold] amplifies every 10 is a tenfold increase
has ossicles
basilar membrane
floor of pond
lined with hair cells
ripples make hair cells bend
inner ear
cochlea
snail shaped tube in inner ear that has a membrane (oval window) which vibrates fluid to fill cochlea
where sound gets tranduced by hair cells
Outer ear
channels sound waves through auditory canal to eardrum
eardrum
membrane that vibrates with waves
middle ear
transmits eardrum’s vibration through a piston made up of 3 bones, hammer, anvil and stirrup
ossicles
3 bones in middle ear that amplify sound (hammer anvil stirrup)
Hair cells
trigger impulses in nerve fibers, sending message
weeds on a pond
sclera
white of an eye
Hearing Message Transmission
sound wave —> outer ear —> ear drum —> middle ear [hammer, anvil, stirrup] —> cochlea [oval window vibrates fluid when it receives vibrations]—> basilar membrane ripples—-> hair cells bend —> nerve fiber impulse triggered —> auditory cortex
Place theory
hear different pitches because activity is triggered at different places
brain recognizes where on basilar membrane receives neural signals
only really works for high pitched sounds
Frequency Theory
neural impulses triggered at same rate as sound wave
pitch determined by frequency of neural impulses
BUT HOW DO WE HEAR PITCH ABOVE 1000 waves/second?
volley principle
volley principle
neural cells alternate firing so the combined is above 1000 waves/second
fire in a series
Locate sounds
having two ears helps
when a sound is on one side, that ear hears it sooner
minute but important
Conduction deafness
problems with mechanical system
(ex. punctured)
hearing aid can restore
nerve deafness
perceptive deafness
sensoineural
damage to hair cell receptors or associated nerves
caused by disease [less common], age [more common] exposure to loud musiv
once cell is dead, it is dead
cochlear implant — sound —> electric
rough approximation
not everyone supports these (national association of Deaf)
Vestibular Sense
balance semicircular canals and vestibular sacks with fluid in them Move > neurons fire eyes help with balance position and motion in a straight line
Motion Sickness
impairment of vestibular sense
conflict between eyes and inner ear
brain “I think I am being poisoned” —> throw up
#borgia
Vertigo
impairment of vestibular sense
severe chronic dizziness
Kinesthetic Sense
tells us where our bodies are in space
receptors—> skin, muscles, joints
receptors —-> detect positions —-> cerebellum —-> thalamus —-> somatosensory cortex
Stimulus of olfactory sense
chemical odors in air
Anatomy and Transmission of Olfactory Sense
Stimulus—> olfactory epithelium[just below frontal lobe transmits along olfactory nerve to amygdala and cortex] —-> receptors [in OE]
epithelium holds receptor cells
only goes to amygdala if emotion attached
prefrontal cortex if pleasant or aversion
olfactory bulb sits below prefrontal cortex
Pheromones
chemical message transmitted between members of same species
path of transmission in Olfactory sense
smell —> olfactory receptors in olfactory epithelium —> olfactory bulb —> olfactory nerve —-> prefrontal cortex —> amygdala
Anosmia
loss of sense of smell
Stimulus of Gustatory sense
chemicals in mouth
Anatomy and message transmission in Gustatory sense
taste receptors, located in taste buds
taste buds - roughly 10000 in mouth, throat, and tongue
taste receptors—> thalamus —> somatosensory cortex in parietal lobe
What kinds of taste receptors are there?
salty sweet sour bitter umami (savory/yummy)
Which sense is the least sensitive?
Gustatory sense?
Which sense is the only one to not send messages to the thalamus?
Olfactory
Olfaction
sense of smell
Supertasters
thin and dislike vegetables more women more likely to be chefs more receptors supersensitivity to taste
Haptic Sense
(skin)
= touch = skin
3 types– pressure, temperature, and pain
skin receptors for diff touch
pressure- diff firing threshold for different parts of body
receptors- blunt and sharp pressure
Sensing temperature
Haptic sense
receptors for warmth and cold
intense can activate both people then feel wetness
Pressure sensation
Haptic Sense
nerve fibers at base of hair follicle respond to hair movement
4 types in skin
Message transmission in Haptic Sense
Skin receptors—> effectors via reflex arc
skin receptors—> thalamus—> limbic
skin receptors—-> thalamus —> somatosensory cortex in parietal lobe
Gate Control Theory of Pain
spinal cord has gates that allow pain messages to pass through
gates are opened by substance P- lack of exercise, anxiety, disuse, thoughts
Gates closed by endorphins, sympathetic ns, relaxation, meditation, thoughts, behavior therapy, and surgery
go into pain
notice contours
relax
pain nerve fibers
two types
fast fibers and slow fibers
fast fibers
sharp and immediate pain
slow nerve fibers
dull and steady pain
chronic pain
Perception
organize, interpret, understanD
Organismic variables or Top Down Processing
processing that uses our experiences and expectations to interpret sensations
Perceptual set/Preceptual expectancy
ex. costume ball vs. seal act
ex. MAC DONALD
MAC HENRY
MAC MAHON
MAC HINERY
ex.
CHO
PHO
USE
ex. Folk
Croak
Soak
schemas
general idea about an object, event, or experience
gender schemas- kids and hair
Frame of Reference
Personal experience form
short to tall
Freshman to senior
Depth Perception
Visual Cliff
Video with googles—> inversion goggles
Monocular cues
Relative Size Interposition Relative Clarity Texture Gradient Relative Height Relative Motion Linear Perspective Relative Brightness
Context
we interpret stimuli by viewing the surroundings
T
C A/H T
E
A 12 B/13 14 C
Bottom Up Processing
data one related in the brain from lower to higher levels of processing
pattern recognition
dog/bear an example of bottom up processing
not the same as context
Template Matching/Prototype Matching
have models to recognize allows us to see things in different forms ex. fingerprints snowflakes "A" in different fonts four wheels + motor = car photos of non-letter letters textbook
Feature Matching
part of bottom-up processing
brail research —-> discovered
feature detector cells + motion detectors
memory stores features and later matches to memory
Attention
auto and controlled processing
how much energy do you need to understand it [stimuli]
Controlled processing (attentive processing)
noticing a stimuli after making conscious effort learning to read sound w. image learning to drive a car write an essay
Automatic Processing (pre-attentive)
notice stimuli without consciously processing it
driving today (not for Olivia and Melissa)
reading today
playing an instrument
Face Perception
type of bottom-up processing
humans discern info, moods, attention, sex, race etc
deficit when you can’t do it
Prosopagnosia
very rare = inability to recognize faces face blindness right hemisphere includes friends, family, spouse stroke/head injury can sometimes lead to this
Monocular Depth Perception
aka Pictorial Depth Cues just need 1 eye 7 Interposition/occlusion relative size familiar size detail/aerial perspective linear perspective texture gradient position relative to horizon
Interposition/Occlusion
overlap near object occludes farther one one object covers all or some barn covers house ---> barn is closer monocular depth perception
relative size
far off project smaller retinal image than closer if they are same size
tiny humans/ bigger humans
monocular depth cue
familiar size
we know how large familiar objects are, so we can judge distance based on retinal image size
markers
tiny humans
monocular depth cue
Detail/aerial Perspective
Further away, more blurry
mountains, closer more visible, farther blurrier
monocular depth cue
Linear Perspective
seemingly parallel lines appear to converge in distance
monocular depth cue
#thatsketchbookassignment
Texture gradient
as a uniformly textured surface recedes, its texture continuously becomes denser
blades of grass clear when close, blurrier when far
fibers in a coat
monocular depth cue
position relative to horizon
monocular depth cue remember when this caused like a revolt in our class and I think Dom had to form like a team to draw 3043424090 diagrams on the board and at least 7 different people tried to explain it?
all else being equal, objects below the horizon that appear high in visual field perceived as farther, objects above horizon low in visual field perceived as being closer
compare below to below and above to above
moon illusion
moon illusion
closer to horizon looks bigger
Binocular Cues
Binocular/Retinal Disparity
convergence
Binocular/Retinal Disparity
each eye has a particular view distance between object and retinal image is different for each eye pencil sausage fingers binocular depth cue
Convergence
as object moves closer, muscles moves eyes toward each other
judge distance based on degree of cross-eyedness
Binocular depth cue
Motion parallax
the relative movement of objects that are at various distances from observer
watching scenery from moving car near objects pass quickly and far objects more slowly (like telephones poles fly by super quickly when near you)
helps brain calculate which objects are closer and which are further away
Motion Cues for depth perception
motion parallax
perceptual constancy
Size perception depends on distance perceptions
Perceptual Constancies
motion cue for depth perception
the brain perceives objects as constant, despite sensory info that could lead it to think otherwise
door still a rectangle even when it moves (shape constancy)
hand same size even if in face (size constancy)
Size perception depends on distance perceptions
farther away the object, then the smaller it is on retina
Optical illusions
fooled by depth cues
Ames Box
Ponzo Illusion
Ames Box
Zimbardo
alter angles in room
Ponzo illusion
same size boxes, but using lines to judge distance. Box takes up more lines
receding parallel lines, same size, but one appears bigger because it sits on receding parallel lines
monsters chasing one another
RECEDING PARALLEL LINES
Muller-Lyer
straight lines with arrows
when arrows point out, looks longer
http://en.wikipedia.org/wiki/M%C3%BCller-Lyer_illusion
Waterfall effects
after effects of motion
spiral demo
spin —> stationary —> move in OPPOSITE direction
Stroboscopic motion perception
motion pictures
flipbook
claymtion
Phi Phenomenon
Phighway signs– highway signs
illusion of movement created by a particular flashing of lights
Induced movement
sit at light car behind you creeps up makes car feel like it is going backwards train station MUST BE STATIONARY
Gestalt Psychology
brain perceives patterns that are more than the sum of their parts the parts are arbitrary
Law of Closure
if something is missing in an otherwise complete figure, our minds tend to add to it
body in box
dashed triangle
Law of Similarity
our minds tend to group similar objects together
lots of ones and zeros = ones and zeros
xs and os
two interlocking pieces
Law of Proximity
objects are seen to belong with objects they are closer to, rather than more distant ones
3 groups vs. 15 dots
2 groups of shapes
group things
Law of Symmetry
Our minds tend to see things as being composed of as many symmetrical figures as possible
[ ][ ][ ]
Law of Continuity
our minds tend to view things as being composed of continuous fiugures
X = / + \
Figure/Ground and reversible figures
skull and face– one seen as figure, other as background or vice verse
both can’t be figures
chalice and faces
illusory contours
NOT CLOSURE
no real shape because not actual shapes
it is the circles with the shaded sectors that looks like it could make a rectangle
Common Movement
Canadian Geese = flock = V
lock at flock
loock at school of fish
look at murder of crows
Necker Cube
wire frame cube with no depth cues
Schroeder stairs
ambiguous figure
no depth cues, we interpret
Hermann grid
black and white with gray blobs
Fechner
big name, founder of psychophysics
pupil
small adjustable opening that light enters through
doesn’t move
iris
a colored muscle that surrounds the pupil and regulates its size and the amount of light it lets in
Lens
behind the pupil focuses the incoming rays into an image by changing its curvature one a light sensitive surface
retina
multilayered tissue that lines the inside of the back of the eyeball that rays focus on
Bipolar cells
intermediaries
next to rods and cones, activate ganglion cells
ganglion cells
make rope like strands that comprise the optic nerve
Optic nerve
carries info to the brain
Blind spot
where the optic nerve leaves the eye and there are no receptor cells
Rods
black and white vision sensitive in dim light periphery
about 120 million
Cones
6-8 million
see color many have their own bipolar cells to relay info precisely and in great detail
Fovea
the retina’s area of central that contains only cones
Oliver Sacks
has prosopagnosia
