unit 6 - sensation & perception Flashcards
sensation
the process by which our sensory receptors and nervous system recieve and represent stimulus energies from our environment
(ex. sight, smell, touch)
perception
the process of selecting, organizing, and interperting sensory information, which enables us to recognize meaningful objects and events
bottom-up processing
a message sent from your senses to your brain
top-down processing
your brain telling your senses what was just experienced
psychophysics
the study of the relationship between physical characteristics of stimuli and our pyschological experience with them
absolute threshold
detect stimuli
- the minimum stimulation needed to detect a particular stimulus 50% of the time
- ex. volume in a car
difference threshold
detect a difference in stimuli
- the minimum difference between two stimuli required for detection 50% of the time
- (just noticiable different - jnd)
subliminal threshold
can’t detect stimuli
- when stimuli are below a person’s absolute threshold
- ex. happening not aware
weber’s law
states that two stimuli need to differ by a certain difference, and not a certain amount to be percieved as different
signal detection theory
a person’s absolute threshold can change depending on the situation they are in
sensory adaption
when you continuously are stimulated by the same stimuli you will stop realizing the stimulation
transduction
the transformation of stimulus energy into neural impulses
phototransduction
the specific transfer of light enerrgy into neural impulses that the brain can understand (vision)
wavelength of lightwave
(aka: length between waves)
- determines the hue (color) of light
- (large wavelength = red; small wavelength = blue/violet)
amplitude of a lightwave
(aka: size of wave)
- related to the brightness of the light
- (high intensity = bright; low intensity = dull)
cornea
transparent tissue where light enters the eye
iris
muscle that expands and contrasts to
pupil
- round opening in the center of your eye
- colored tissue that makes “eye color”
lens
focuses the light rays on the retina
retina
contains sensory receptors that process visual information and sends it to the brain
accommodation
the process by which the eye’s lens changes shape to help focus near or far objects on the retina
bipolar cells
goes from bipolar cells to ganglion cells
ganglion cells
comes from bipolar cells
fovea
central point in the retina around which the eyes cones cluster
optic nerve
- carries neural impulses from the eye to the brain
- creates blind spots
thalamus
recieves information from the senses (except smell) and routes it to the brain to figure out what is going on
(sensory switchboard)
occipital lobe
(back head)
visual function (vision)
blindspot
a break in the visual field
nearsighted
if you can see near objects but far objects are blurry
farsighted
if you can see far objects but near objects are blurry
rods & cones
- rods/cones transduce light to color and brightness
- you have more rods than cones
- cones in the center of the retina, rods in the periphery
- cones see in color, rods don’t
- rods see in the dark, cones don’t
feature detectors
nerve cells in the visual cortex respond to specific features, such as edges, angles, and movement.
shape detectors
specific combinations of temporal lobe activity occur as people look at different important objects.
parallel processing
- processing of several aspects of the stimulus simultaneously
- the brain divides a visual scene into sub-divisions such as color, depth, form, and movement.
young-helmoltz trichomatic theory
- states that there are cones for: blue, green, and red.
- every other color you can see is a combination of those.
subtraction of colors
- paints/pigments
- three primary colors: red, blue, yellow
- when you combine paints you subtract wavelength, so you end up with black.
addition of colors
- when dealing with light the three primary colors are: blue, red, and green.
- when you mix light you add wavelength so when all are mixed together you end up with white.
color blindness
- genetic disorder in which people are blind to green or red colors.
- this supports the trichromatic theory.
opponent process theory
process that four colors are seen by the ganglion cells combined in pairs of red-green, blue-yellow, and black-white
color constancy
- color of an object remains the same under different illuminations
- however, when context changes the color of an object may look different
sound waves
composed of compression and rarefaction of air molecules
acoustical transduction
conversion of sound waves into neural impulses in the hair cells of the inner ear
wavelength of sound waves
the distance from the peak of one wave to the peak of the next determines the pitch
amplitude of sound waves
- amount of energy in a wave, determined by the amplitude, relates to the perceived loudness
- the taller the wave the louder the sound.
pinna
fleshly outer part of your ear
auditory canal
the hole in your ear
eardrum
the vibrating part of your ear
ossicles (three tiny bones: hammer, anvil, stirrup)
firing back and fourth
oval window
a membrane covering the entrance to the cochlea in the inner ear
cochlea
coiled, bony, snail-like fluid-filled tube in the inner ear that transforms sound vibrations to auditory signals.
basilar membrane
the main mechanical element of the inner ear
(hair cells = transduction)
transduction
temporal lobe
(side of head)
auditory function (hearing)
place theory
there are hair cells for high pitches and hair cells for low pitches, it depends where the stimulation happens.
frequency theory
all hair cells can hear all pitches, it just depends on how fast the hair cells are stimulated that allow one to hear different pitches.
sound localization
because we have two ears, sounds that reach one ear faster than the other ear cause us to localize the sound.
factors that allow us to localize sound
intensity differences (one ear hears it louder)
time differences (one ear hears it sooner)
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
sensorineural hearing loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerve, also called nerve deafness
4 basic touch sensation
pressure, warmth, cold, and pain
gate-control theory of pain
there is a gate on our spinal cord that when open sends pain, but when shut blocks pain
methods that can reduce pain
drugs, surgery, acupuncture, exercise, hypnosis, and even though distraction
5 basic taste sensations
sweet, sour, salty, bitter, umami (fresh chicken)
gustatory system
taste
sensory interaction
when senses work together, such as, taste and smell
olfactory system
smell
kinethesis
knowing how your body is positioned in space
vestibular system
located behind the ear is in control of your balance
selective attention
- perceptions about objects change from moment to moment
- we can perceive different forms of the necker cube; however, we can only pay attention to one aspect of the object at a time.
cocktail party effect
when there is a lot of people, you get to decide which conversation you listen to and don’t listen to the other ones
inattentional blindness
the inability to see an object or a person in our midst
change blindness
a form of inattentional blindness in which something is seen, but changes, and the person can’t notice the change.
visual capture
when vision competes with our other senses, vision usually wins
gestalt psychology
Gestalt psychologists showed that a figure formed a “whole” different than its surroundings.
figure-ground
figure = what you’re concentrating on
ground = everything in the background
proximity
close things are grouped together
(other Gestalt principles of organization)
similarity
similar things are grouped together
(other Gestalt principles of organization)
closure
things that are almost finished are “finished” by the mind
(other Gestalt principles of organization)
continuity
things that start seem like they should continue
(other Gestalt principles of organization)
connectedness
things that are connected are grouped together
(other Gestalt principles of organization)
depth perspective
allows us to judge distances
visual cliff
psychological studies done with a visual cliff (Gibson & Walker) help point to the fact that infants have that ability as well
monocular cues
depth perception with one eyes
biocular cues
depth perception with two eyes
retinal disparity
- a human’s 2 retinas send the brain two different pictures
- the brain tells the slight differences between the two pictures and judges depth
convergence
when objects are close the eyes move together, when they are far away the eyes spread apart, this sends info to the brain about how close or far an object is
relative size
if two objects look alike, the bigger one seems closer
interposition
an object that blocks another object seems like its closer
relative clarity
clear things seem close, fuzzy things seem far away
texture gradient
detailed things seem close, non-detailed things seem far away
relative height
objects high up in our visual field of vision seem farther than objects that are low in our field of vision
relative motion
when moving, and staring at a fixed point, everything above it seems to move with you, everything below it seems to move away from you
linear perspective
parallel lines appear to converge in the distance, the closer the lnes appear to be the further away it seems
light and shadow
bright things seem close, dark things seem far away
immanuel kant’s (nature) view of perception
- perception is inborn
- nature
john locke’s (nurture) view of perception
- perception is learned
- nurture
restored vision
(what do those with restored vision see (used to be blind..)?
after cataract surgury, blind adults were able to regain sight
these individuals could differentiate figure and ground relationships, yet they had difficulty distinguishing a circle and triangle
facial recognition
(what do those with restored vision see (used to be blind..)?
after blind adults regained sight, they were unable to recognize entire faces
sensory deprivation
(what do those with restored vision see (used to be blind..)?
kitten raised without exposure to horizontal lines later had difficulty perceiving horizontal bars
perceptual adaption
a visual ability to adjust to an artificially displaced visual field
(ex. glasses that throw you off by 30 degrees)
perceptual set
when people believed that they had seen the loch ness monster they were likely experiencing it
where they had a mental predisposition to perceive one thing and not the other
schemas on facial recognition
children’s schemas for faces develop earlier than other body parts
face schemas are created by distinct features of the face
schemas and concepts that organize and interpret unfamiliar information
context effects
the context of something can effect how you perceive it
cultural context
likewise, if your culture determines what you see
human factor psychologists
design machines that assist our natural perceptions
extrasensory perception (ESP)
perception without sensory input
telepathy
potential types of ESP
- mind-to-mind communication
- one person sending thoughts and the other recieving them
clairvoyance
potential types of ESP
knowing what’s happening in the outside world without seeing or hearing it
precognition
potential types of ESP
preceiving future events
does ESP work?
most psychologists today do not believe in ESP:
- they believe people claiming ESP are very skilled at deception
- ESP has not been proven in psychological laboratories
