sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
sensory receptors
sensory nerve endings that respond to stimuli
perception
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
bottom-up processing
analysis that begins with the sensory receptors and works up to the brain's integration of sensory information
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations
selective attention
the focusing of conscious awareness on a particular stimulus
cocktail party effect
ability to attend to only one voice in a sea of other voices
divided attention
the ability to carry out multiple tasks at once; interfere if overlapping
inattentional blindness
failing to see visible objects when our attention is directed elsewhere
change blindness
failing to notice alterations in our environment, ex: choice blindness
transduction
conversion of one form of energy into another
Psychophysics
the study of relationships between the physical properties of stimuli and our psychological experience
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50 percent of the time
signal detection theory
a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation
4 reasons for signal detection theory
experience, expectations, motivation, and alertness
subliminal
below one's absolute threshold for conscious awareness
priming
the activation, often unconsciously, of certain associations, predisposing one's perception, memory, or response
difference threshold
the minimum difference between two stimuli required for detection 50 percent of the time
webers law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage
sensory adaptation
diminished sensitivity as a consequence of constant stimulation
perceptual set (ps)
a mental predisposition to perceive one thing and not another
ps context effects
stimuli affected by whats around it
ps motivation
motivation changes from one thing after seeing another
ps emotion
feelings about the world make you see your emotions everywhere
esp
extrasensory perception; the claim that perception can occur apart from sensation
telepathy
mind to mind communication
clairvoyance
the ability to see remote events
precognition
the ability to predict the future
parapsychology
the study of paranormal phenomena
Wavelength
the distance from peak to peak of a wave; determines color in lightwaves
hue
the dimension of color that is determined by wavelength; red, blue, green, magenta, yellow, cyan
intensity
the amount of energy in a wave as determined by the waves amplitude (height)
cornea
a clear protective layer that covers the iris and pupil
aqueous humor
a gel layer between the iris and pupil
pupil
the adjustable opening in the center of the eye through which light enters
iris
a ring shaped colored muscle that controls the size of the pupils opening
lens
the transparent structure behind the pupil that changes shape to help focus images on the retina
accomodation
the process by which the eye's lens changes shape to focus on images near and far
retina
the light-sensitive inner surface of the eye, containing the rods and cones and layers of neurons that begin the processing of visual information
rods
receptors in the retina that detect gray scale and movement and provide peripheral and twilight vision
cones
receptors in the retina that detect fine detail and color in daylight or well-lit conditions
optic nerve
the nerve that carries neural impulses from the eye to the brain
blind spot
the point at which the optic nerve leaves the eye, creating a spot with no retinal receptors
fovea
the focal point in the retina around which the eyes cones cluster
feature detectors
nerve cells in the brain's visual cortex that respond to specific features of a stimulus, such as shape, angle, or movement
Young-Helmholtz trichromatic theory
the theory that the retina contains three different color receptors; red, green and blue, which, when stimulated in combination, can produce the perception of any color.
opponent-process theory
the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision
gestalt
an organized whole; necker/impossible cube
figure-ground
the organization of the visual field into objects that stand out from their surroundings
grouping
the perceptual tendency to organize stimuli into coherent groups
depth perception
the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance
visual cliff
a laboratory device for testing depth perception in infants and young animals
binocular cues
depth cues that use both eyes
retinal disparity
by comparing retinal images from each eye the brain can judge distance
monocular cues
depth cues using one eye
Interposition
objects that are partially blocked are perceived as farther away than complete objects
relative height
we perceive objects higher in our field of vision as farther away
relative motion (motion parallax)
As we move, objects that are actually stable may appear to move; close objects appear to move backwards, objects in the distance appear to move slowly with us
relative size
assuming objects are similar in size, the object that is larger is perceived to be closer
linear perspective
parallel lines appear to converge with distance; the sharper the angle of convergence, the greater the perceived distance
lights and shadows
shading produces a sense of dept, consistent with our assumption that light comes from above
phi phenomenon
an illusion of movement created when two or more adjacent lights blink on and off in quick succession
perceptual constancy
perceiving objects as unchanging even as sensation changes
shape constancy
perceiving the shape of an object as unchanging even as retinal images of the shape change
color constancy
perceiving the color of an object as unchanging even as retinal images of the color change
brightness constancy
perceiving an object as having unchanging brightness even as reflective wavelengths of light alter
ames room
an optical illusion
perceptual adaptation
the ability to adjust to changing sensory input
audition
the sense or act of hearing
frequency
the number of complete wavelengths that pass a point in a given time
pitch
a tones perceived highness or lowness as determined by frequency
timbre
the quality or a sound distinct from its pitch and loudness
outer ear
the ear cartilage and ear canal; funnels soundwaves towards the middle ear and inner ear
middle ear
ear drum(tympanic membrane), malleus (the hammer) the incus (anvail, stirrup) function- helps concentrate vibrations of the ear drum on the cochleas oval window
inner ear
contains the cochlea, semi circular canals, and the vestibular sacs; processing sound begins
conductive/conduction hearing loss
hearing loss caused by damage to the mechanical systems that conduct sound waves to the cochlea
sensory neural hearing loss
caused by damage to the cochleas receptor cells or auditory nerve
cochlea
a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
perception of sound (timbre)
frequency determines pitch, amplitude determines loudness or volume (dB decibels)
place theory (basilar membrane)
the theory that links the pitch we hear with the spot where the cochleas basilar membrane is stimulated (high frequencies not low)
frequency theory
the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone (low frequencies not high)
volley principle
the theory that the nerve impulses of the auditory nerve are combined
touch
a sensation within your skin
temperature
thermal receptors adapt to temp easily
sense of pressure
2 levels of pressure; meissner corpuscule- light pressure, pacinion corpuscule- hard pressure
pain
nociceptors
gate control theory of pain
the theory that the spinal cord contains a neurological gate that either blocks pain signals or allows that to travel to the brain
phantom limb syndrome
when people who are lacking limbs continue to report sensations in those limbs
social-critical incfluences on pain
what pain are we allowed to feel
gustation
sense of taste
sweet
detects energy sources
salty
good for physiological functions
sour
detects potentially toxic acids
bitter
detects potential poisons
umami
detects proteins
olfaction
sense of smell; olfactory bulb- concentration of olfactory nerves above the nose
kinesthesia
our sense of movement and body position
vestibular sense
sense of body position and balance
sensory interaction
the principle that one sense may depend on another