Ch 3 Sensation and Perception Flashcards
brightness
amplitude of a light wave
color
wavelength of a light wave
saturation
perceived purity of color
pupil
dilates to allow different amounts of light in
iris
muscles control pupil size
aqueous humor
clear liquid at front of eye, provides nourishment
cornea
bends light to hit retina
vitreous humor
jelly liquid in center of eye that provides shape
lens
changes shape to focus on object
retina
photoreceptor cells for light processing
optic nerve
sends info from photoreceptors
visual accomodation
lens changes thickness to focus on objects; people lose ability for lens to accommodate, need glasses
rods
see black and white, have low sharpness, good at low light levels
cones
fine detail in light, see color and movement
how the eye sees
separates into left and right visual fields, the cornea sees a flipped image, brain accommodates; each visual cortex gets half of the image
dark adaptation
when rods in the eye slowly takeover vision
trichromatic theory
three cones for red, blue, and green; brain computes color from amount of light the cone gets and how fast it fires (wavelength)
opponent-process theory
accounts for afterimages; red and green vs blue and yellow and are paired as opposites; when one is stimulated the other is inhibited
color blindness
occurs when cones are defective
humonculus
areas of the body with concentrated nerve endings where sensations are more sensetive
what is sound
the vibrations of molecules
pitch
wavelength of sound
timbre
richness of sound
volume
amplitude of sound
frequency of sound
determines the sounds you can hear
pinna
outer part of the ear that funnels sound
auditory canal
tunnel to the eardrum
eardrum parts
hammer, anvil, stirrup
eardrum
three bones in the ear vibrate from sound and amplify the vibrations, vibrates the oval window
oval window
makes fluid in the cochlea vibrate
cochlea
fluid sac with basilir membrane inside
basilir membrane
vibrates organ with hair cells that are sound receptors
pitch of sound and anatomy: place theory
place theory where hair cells are stimulated, the closer to the oval window, the higher the pitch
pitch of sound and anatomy: frequency theory
frequency theory where basilir membrane vibrates, the faster it vibrates the higher the pitch
pitch of sound and anatomy: volley principle
three groups of neurons fire in succession dividing the frequency so certain neurons create different sounds
pitch of sound and anatomy: correctness
place theory works for high pitch, frequency theory works for low pitch, volley theory accounts for ringing in the ears
conduction hearing impairment
vibrations don’t transfer to the cochlea
nerve hearing impairment
permanent damage to ear neurons or the brain receptors after high volume
taste receptors
taste is called gustation, receptors are taste buds; people have different numbers
papillae
bumps on tongue that are lined by taste buds, each have about 20 neurons; they’re replaced every week or so
papillae function
have chemical receptors that are activated by food, sent to brain and limbic system; enhanced by smell
Five tastes
sweet, sour, salty, bitter, umami; receptors for all tastes found everywhere
food texture
sensed by the somatosensory cortex
receptors cells for smell
have cells at the top of the nasal canal and there are around 10 million; the cells are small hairs that collect molecules; over 1000 smells; replaced 5-8 weeks
somesthetic senses
skin, kinesthetics, vestibular sensing
skin sense
nerves are below the skin surface; nerves are connected to the hair follicles; senses pain
somatic pain
senses if somethings about to be damaged or if it has been damaged and needs to be protected
visceral pain
internal organ pain
theories of pain: gate-control theory
pain passes through the spinal cord and allows pain to pass or inhibit
spinal cord and pain
pain receptor cells release substance P and activates the neurons in the spinal cord to tell the brain
kinesthetic sense
receptors in muscles, tendons, and joints tell the body its position in space in relation to eachother; ex. raising your hand while closing your eyes
vestibular sense
sense located in inner ear; impacts balance and body position
otolith organs
sacs above the cochlea, filled with liquid and crystals; when we move, the crystals vibrate and sends info to the brain
semicircular canals
three canals in the ear that have all three dimensional planes, fluid rotates in the canals
perception
the method by which the brain takes all the sensation a person experiences
constancy
when stimuli stay the same
size constancy
same size object no matter the distance
shape constancy
interpret a shape the same way no matter the view angle
brightness constancy
perceiving brightness even when light conditions change
cocktail party effect
focusing on a single stimulus and blocking out background stimuli
figure-ground relationship
objects are always seen as being on a background
proximity constancy
objects close together are automatically grouped
similarity constancy
objects that appear similar are grouped (ie uniformed sports team)
closure constancy
tendency to complete incomplete figures
continuity constancy
easier to group things simpler than to see them separately completely
contiguity constancy
connecting two events close in time as related
common region constancy
when objects are in a common area they are grouped
depth perception
being able to see 3-D; two ways: monocular or binocular cues
monocular cue
clues from seeing with one eye; see pictorial depth cues; how paintings create depth in pictures
linear perspective: monocular
too parallel lines seemingly converge
relative size: monocular
smaller figures are farther away
overlap: : monocular
items blocked are perceived as farther away
aerial perspective: monocular
from above, the farther away the object the hazier it appears
texture gradient: monocular
closer textures are distinct; farther texture is smaller and finer
motion parallax: monocular
in a moving car, closer objects move faster than further objects
accomodation: monocular
when lens changes to focus on object and it’s distance; brain interprets the distance
convergence: binocular
both eyes work together and put together the image; brain interprets the distance
binocular disparity: binocular
both eyes see different images; brain interprets the distance; the closer the object the more different the image
Psychophysics
study of stimuli and the resulting perceptions and sensations
Absolute threshold
lowest level of stimulation that can be detected 50% of the time
Just Noticeable Difference threshold
the amount a stimuli must be changed in order to detect a difference 50% of the time
Signal detection theory
there are four categories of the types of reaction to stimuli: hit, miss, false alarm, correct rejection
Weber’s Law
there is a constant applied to the just noticeable difference that says when a stimuli will be perceived as different
Fechner’s Law
sensation is proportional to the log of the stimulus’ intensity
Steven’s Power Law
sensation is an exponential relationship with the stimulus’ intensity
Transduction
transfer of the energy of the stimulus into the neuroreceptors and brain response
receptor cells in the eye
bipolar, to ganglion, to amacrine
sound localization
ability to detect where a sound is coming from
tympanic membrane
outer membrane connecting the parts of the ear drum
ossicles
the three bones within the ear drum
visual cliff
test of depth perception
