Unit Three test Flashcards
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
inattentional blindness
failing to see visible objects when our attention is directed elsewhere
change blindness
failing to notice changes in the environment; a form of inattentional blindness
transduction
in sensation, the transforming of stimulus energies, such as sights and sounds, into neural impulses our brains can interpret
absolute threshold
the minimum stimulus energy needed to detect a particular stimulus 50 percent of the time
signal detection theory
a theory that assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness
difference threshold
the minimum difference between two stimuli required for detection; sometimes called the just noticeable difference (j.n.d.)
Weber’s Law
the principle that, to be perceived as different, two stimuli must differ by a constant percentage (rather than a constant amount)
sensory adaptation
diminished sensitivity as a consequence of constant stimulation (e.g. getting used to the temperature of a pool)
perceptual set
a mental predisposition to perceive one thing and not another
cornea
the eye’s clear, protective outer layer, covering the pupil and iris
pupil
the adjustable opening in the center of the eye through which light enters
iris
a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
lens
the transparent structure behind the pupil that changes shape to help focus images on the retina
accommodation
the process by which the eye’s lens changes shape to focus near or far objects on the retina
retina
the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information
rods
retinal receptors that detect black, white, and gray, and are necessary for peripheral and twilight vision
cones
retinal receptor cells that detect fine detail and give rise to color sensations
optic nerve
the nerve that carries neural impulses from the eye to the brain
fovea
the central focal point in the retina, around which the eye’s cones cluster
parallel processing
processing many aspects of a problem simultaneously; the brain’s natural mode of information processing for for many functions, including vision
Young-Helmholtz trichromatic theory
the theory that the retina contains three different types of color receptors (one most sensitive to red, one to green, one to blue) which, when stimulated in combination, can produce the perception of any color
opponent-process theory
the theory that opposing retinal processes (red-green, blue-yellow, black-white) enable color vision; this theory explains negative afterimages
audition
the sense or act of hearing
frequency
the number of complete wavelengths that pass a point in a given time
pitch
a tone’s experienced highness or lowness; depends on frequency
eardrum
a tight membrane located at the end of the ear canal that vibrates when struck by sound waves
middle ear
the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window
cochlea
a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
semicircular canals
three fluid-filled canals in the inner ear responsible for our sense of balance
sensorineural hearing loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; the most common form of hearing loss, also called nerve deafness
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
place theory
in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated
frequency theory
in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch
gate-control theory
the theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain
nociceptors
sensory receptors that enable the perception of pain in response to potentially harmful stimuli
gustation
the sense of taste
olfaction
the sense of smell
kinesthesia
our movement sense; our system for sensing the position and movement of individual body parts
vestibular sense
our sense of body movement and position that enables our sense of balance
sensory interaction
the principle that one sense may influence another, as when the smell of food influences its taste
synesthesia
a phenomenon where the stimulation of one sense (such as hearing sound) triggers an experience of another (such as seeing color)
Gestalt psychology
an early perspective in psychology that focused particularly on the perception of integrating pieces into meaningful wholes
law of proximity
Gestalt principle of grouping nearby figures together
law of continuity
Gestalt principle of perceiving smooth, continuous patterns rather than discontinuous ones
closure
Gestalt principle of filling in gaps to create a complete, whole object
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 cue
a depth cue, such as retinal disparity, that depends on the use of two eyes
Retinal disparity
by comparing retinal images from the two eyes, the brain computes distance; the greater the disparity (difference) between the two, the closer the object
monocular cue
a depth cue, such as interposition, available to either eye alone
relative height
a depth cue stating we perceive objects higher in our field of vision as farther away
relative size
a depth cue stating if we assume two objects are similar in size, we perceive the one that appears smaller as farther away
interposition
a depth cue stating if one object partially blocks our view of another, we perceive it as closer
perceptual constancy
perceiving objects as unchanging (having consistent color, shape, and size) even as illumination and retinal images change
linear perspective
a depth cue stating parallel lines appear to meet in the distance; the sharper the angle of convergence, the greater the perceived distance
perceptual adaptation
the ability to adjust to changed sensory input, including an artificially displaced or even inverted visual field
extrasensory perception (ESP)
the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition
parapsychology
the study of paranormal phenomena, including ESP and psychokinesis
telepathy
mind-to-mind communication
precognition
perceiving future events, such as an unexpected death in the next month
clairvoyance
perceiving remote events, such as a house on fire in another state
Auditory nerve
connects to and sends signals to the brain
