Chapter 5 Key Terms Flashcards
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
sensation
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
perception
analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information
bottom-up processing
information processing guided by the higher-level mental processes, as when we construct perceptions drawing on our own experiences and expectations
top-down processing
have complete sensation, but incomplete perception;Sense visual info, but can’t recognize it; cannot process top-down (cannot relate stored knowledge to sensory input)
prosopagnosia
the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them
psychophysics
the minimum stimulation needed to detect a particular stimulus 50 percent of the time
absolute threshold
a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation ; assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and level of fatigue
signal detection theory
faint stimulus
signal
background stimulation
noise
below one’s absolute threshold for conscious awareness
subliminal
the activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response
priming
the minimum difference between 2 stimuli required for detection 50 percent of the time; we experience it as a just noticeable difference
difference threshold
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)
Weber’s Law
diminished sensitivity as a consequence of constant stimulation
sensory adaptation
conversion of one form to another; in sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret
transduction
the distance from the peak of one light or sound wave to the peak of the next; vary from short blips of cosmic rays to the long pulses of radio transmission
wavelength
the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, etc
hue
the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave’s amplitude
intensity
height of wave
amplitude
light enters the eye through it, protects the eye and bends light to provide focus
cornea
the adjustable opening in the center of the eye through which light enters
pupil
a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
iris
the transparent structure behind the pupil that changes shape to help focus images on the retina
lens
the process by which the eye’s lens changes shape to focus near or far objects on the retina
accommodation
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
retina
sharpness of vision (affected by small distortions in the eye’s shape)
acuity
a condition in which nearby objects are seen more clearly than distant objects because distant objects focus in front of the retina
nearsightedness
a condition in which far away objects are seen more clearly than near objects because the image of near objects is focused behind the retina
farsightedness
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don’t respond
rods
retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions; they detect fine detail and give rise to color sensations
cones
the nerve that carries neural impulses from the eye to the brain
optic nerve
point at which the optic nerve leaves the eye, no receptor cells are located there
blind spot
the central focal point in the retina, around which the eye’s cones cluster
fovea
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
feature detectors
step by step processing computers do
serial processing
the processing of several aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions, including vision; contrasts with step by step serial processing of most computers and of conscious problem solving
parallel processing
blindness in part of their field of vision, there’s a parallel processing system operating unseen
blindsight
theory that the retina contains 3 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
Young-Helmholtz trichromatic (three-color) theory
subtracts wavelengths from the reflected light
Subtractive color mixing
adds wavelengths and increases the light
Additive color mixing
when you stare at one color for a long time and then look at a white paper, you will see its opponent color
afterimages
theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision; some cells are stimulated by green and inhibited by red, others are stimulated by red and inhibited by green
opponent-process theory
perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object
color constancy
the sense or act of hearing (highly adaptive)
audition
the number of complete wavelengths that pass a point in a given time
frequency
a tone’s experienced highness or lowness; depend on the frequency
pitch
measuring unit for sound energy
decibels
channels sound waves through the auditory canal
outer ear
tight membrane that vibrates with the waves
eardrum
chamber b/w the eardrum and cochlea containing 3 tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window
middle ear
coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses
cochlea
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs
inner ear
in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated
place 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
frequency theory
neural cells can alternate firing
volley principle
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea (Ability to conduct vibrations diminishes)
conduction hearing loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves
Sensorineural hearing loss (nerve deafness)
device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
Cochlear implant
extreme sensitivity to pain, makes life miserable
Hyperalgesia
perceive sensations in nonexisting limbs; misinterpret CNS activity
phantom sensations
phantom sounds, ringing in the ears, for people with hearing loss
tinnitus
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
Gate-control theory
the principle that one sense may influence another, as when the smell of food influences its taste
sensory interaction
seeing a speaker say one syllable and hearing another, we may perceive a third syllable that blends both inputs
McGurk effect
one sort of sensation produces another
Synaesthesia
system for sensing the position and movement of individual body parts
kinesthesis
sense of body movement and position, including the sense of balance
vestibular sense
