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
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
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
Weber's law
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 wavelengths 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
accommodation
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
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
blind spot
fovea
the central focal point in the retina, around which the eye's cones cluster
feature detectors
parallel processing
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
color constancy
perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object
audition
the sense or act of hearing
frequency
the number of complete wavelengths that pass a point in a given time
pitch
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
inner ear
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
sensorineural hearing loss
cochlear implant
gate control theory
theory that spinal cord contains neurological gate that blocks pains signals or allows them to pass. gate is opened by activity of pain going up small nerve fibers & gate is closed by act of large fibers or by info coming from brain
sensory interaction
kinesthesis
the system for sensing the position and movement of individual body parts
vestibular sense
gestalt
figure-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 and convergence, that depend on the use of two eyes
retinal disparity
a binocular cue for perceiving depth; by comparing images from the two eyeballs, the brain computes distance - the greater the disparity (difference) between the two images, the close 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
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
human factors psychology
extrasensory perception (ESP)
parapsychology
the study of paranormal phenomena, including ESP and psychokinesis