Studied by 1 PersonTags & Description
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.
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.
psychophysics
the study of relationships between the physical characteristics of stimuli such as their intensity and our psychological experience of them.
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 (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
priming
the activation often unconsciously of certain associations thus predisposing one's perception memory or response.
difference threshold
the minimum difference between two stimuli required for detection 50 percent of the time. Also called the just noticeable difference (jnd).
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.
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 brains can interpret.
wavelength
the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic versions of this vary from the short blips of cosmic rays to the long pulses of radio transmission.
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.
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.
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.
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.
accomodation
the process by which the eye's lens changes shape to focus near or far objects on the retina.
rods
retinal receptors that detect black white and gray necessary for peripheral and twilight vision when cones don't respond.
cones
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. These detect fine detail and give rise to color sensations.
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 and no receptor cells are located there.
fovea
the central focal point in the retina around which the eye's cones cluster.
feature detectors
nerve cells in the brain that respond to specific features of the stimulus such as shape angle or movement.
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.
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.
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.
audition
the sense or act of hearing.
frequency
the number of complete wavelengths that pass a point in a given time (for example per second).
pitch
a tone's experienced highness or lowness depends on frequency.
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
inner ear
the innermost part of the ear containing the cochlea semicircular canals and vestibular sacs.
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.
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 nerves also called nerve deafness.
cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea.
kinesthesis
the system for sensing the position and movement of individual body parts.
vestibular sense
the sense of body movement and position including the sense of balance.
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.
sensory interaction
the principle that one sense may influence another as when the smell of food influences its taste.
gestalt
an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes
figure-ground
the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground).
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 such as retinal disparity that depend on the use of two eyes.
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.
monocular cues
depth cues such as interposition and linear perspective available to either eye alone.
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 (having consistent shapes size lightness and color) even as illumination and retinal images change.
color constancy
perceiving familiar objects as having consistent color even if changing illumination alters the wavelengths reflected by the object.
perceptual adaptation
in vision the ability to adjust to an artificially displaced or even inverted visual field.
perceptual set
a mental predisposition to perceive one thing and not another.
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.
Gestalt Principles
Principles that describe the brain's organization of sensory information into meaningful units and patterns.
proximity
nearness
similarity
the tendency to perceive things that look similar to each other as being part of the same group
Continuity
the tendency to perceive things as simply as possible with a continuous pattern rather than with a complex broken-up pattern
Connectedness
Gestalt grouping principle when objects uniform (in color or texture) are linked (no space exists between them) we perceive them as a single unit
Closure
we fill in gaps to create a complete whole object
relative size
a monocular cue for perceiving depth the smaller retinal image is farther away
Interposition
monocular visual cue in which two objects are in the same line of vision and one patially conceals the other indicating that the first object concealed is further away
relative clarity
a monocular cue for perceiving depth hazy objects are farther away than sharp clear objects
relative motion (motion parallax)
Monocular distance cue based on the fact that moving objects appear to move a greater distance when they are close to the viewer than when they are far away
linear perspective
A monocular cue for perceiving depth the more parallel lines converge the greater their perceived distance.
light and shadow
a monocular cue for perceiving depth a dimmer object seems farther away
convergence
A binocular cue for perceiving depth the extent to which the eyes converge inward when looking at an object
light waves
electromagnetic waves that stimulate receptors in the eye
Thalamus
the brain's sensory control center located on top of the brainstem it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla
occipital lobe
A region of the cerebral cortex that processes visual information
occiptal cortex
vision
bipolar cells
In the retina the specialized neurons that connect the rods and cones with the ganglion cells.
ganglion cells
In the retina the specialized neurons that connect to the bipolar cells the bundled axons of the ganglion cells form the optic nerve.
Color
An element of art that is derived from reflected light
Amplitude
Height of a wave