Sensation and Perception Flashcards
embodied cognition
in psychological science, the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.
place theory
in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated.
feature detectors
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement.
kinesthesis
the system for sensing the position and movement of individual body parts.
monocular cues
depth cues, such as interposition and linear perspective, available to either eye alone.
fovea
the central focal point in the retina, around which the eye’s cones cluster.
parallel processing
the processing of many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions, including vision. Contrasts with the step-by-step (serial) processing of most computers and of conscious problem solving.
lens
the transparent structure behind the pupil that changes shape to help focus images on the retina.
sensorineural hearing loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; also called nerve deafness.
bottom-up processing
analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information.
binocular cues
depth cues, such as retinal disparity, that depend on the use of two eyes.
perceptual constancy
perceiving objects as unchanging (having consistent shapes, size, brightness, and color) even as illumination and retinal images change.
sensory adaptation
diminished sensitivity as a consequence of constant stimulation.
Young-Helmholtz trichromatic (three-color) theory
the theory that the retina contains three different 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.
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.
cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea.
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.
audition
the sense or act of hearing.
retinal disparity
a binocular cue for perceiving depth: By comparing images from the retinas in the two eyes, the brain computes distance- the greater the disparity (difference) between the two images, the closer the object.
cones
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.
optic nerve
the nerve that carries neural impulses from the eye to the brain.
frequency
the number of complete wavelengths that pass a point in a given time (for example, per second).
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50 percent of the time.
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.
parapsychology
the study of paranormal phenomena, including ESP and psychokinesis.
difference threshold
the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (or jnd).
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; necessary for peripheral and twilight vision, when cones don’t respond.
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.
color constancy
perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object.
gestalt
an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes.
hue
the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth.
cochlea
a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses.
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. The “gate” is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.
perceptual set
a mental predisposition to perceive one thing and not another.
phi phenomenon
an illusion of movement created when two or more adjacent lights blink on and off in quick succession.
inner ear
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.
visual cliff
a laboratory device for testing depth perception in infants and young animals.
opponent-process theory
the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green.
extrasensory perception (ESP)
the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition.
perceptual adaptation
in vision, the ability to adjust to an artificially displaced or even inverted visual field.
figure-ground
the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground).
sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
perception
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.
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.
wavelength
the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission.
intensity
the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave’s amplitude.
Weber’s law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount).
pitch
a tone’s experienced highness or lowness; depends on frequency.
pupil
the adjustable opening in the center of the eye through which light enters.
transduction
conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.
psychophysics
the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
blind spot
the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there.
signal detection theory
a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness.
subliminal
below one’s absolute threshold for conscious awareness.
sensory interaction
the principle that one sense may influence another, as when the smell of food influences its taste.
accommodation
the process by which the eye’s lens changes shape to focus near or far objects on the retina.
vestibular sense
the sense of body movement and position, including the sense of balance.
grouping
the perceptual tendency to organize stimuli into coherent groups.
priming
the activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response.
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.
