ch.6- Sensation and Perception Flashcards
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
bottum-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
a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation(noise).
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
weber’s law
to be perceived as different, 2 stimuli must differ by a constant rather than a constant amount
transduction
conversion of 1 form of energy to another(transform stimulus energies into neural impulses)
wavelength
distance from peak of one light or sound wave to the next
hue
dimension of color that is determined by wavelength of light
intensity
amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave’s amplitude
pupil
adjustable opening in the center of the eye through which light enters
iris
ring of muscle tissue that forms the colored portion of the eye around 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
lens
the transparent structure behind the pupil that changes shape to help focus images on the retina
accommodation
te process by which the eye’s lens changes shape to focus near or far objects on the retina
rods
receptor cells that detect black, white, and gray, necessary for night vision
cones
receptor cells in the center of the retina, function in well-lit conditions, detect fine detail and color
optic nerve
the nerve that carries neural impulses from the eye to the brain via the thalamus
blind spot
the point at which the optic nerve leaves the eye, creating a “blind” spot because 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
opponent-process theory
the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. Fore example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
young-helmholtz trichromatic (3 color) theory
the theory that the retina contains 3 different color receptors- one most sensitive to res, one to green, one to blue- which, when stimulated in combination, can produce the perception of any color
pitch
a tone’s experienced highness or lowness; depends on frequency
frequency
the number of complete wavelength that pass a point in a given time (for example, per second)
middle ear
the chamber between the eardrum and chattel containing 3 tiny bones (hammer, anvil, stirrup) that concentrate the vibrations o the eardrum on the cochlea’s oval window
cochlea
a coiled bony fluid-filled tube in the air 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 yo the auditory nerve matches the frequency of a tone, thus enabling s 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
sensorineural hearing loss
hearing loss caused by the damage to the cochlea’s receptor cells of to the auditory nerves; also called nerve deafness
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
vestibular sense
tye sense of body movement and position including the sense of balance
kinesthesis
the system for sensing the position and movement of individual body parts
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 the pain signals traveling up small nerve fibers and is closed by the activity in larger fibers or by information coming from the brain
figure-ground
the organization of the visual field objects (the figures) that stand out from their surroundings (the ground)
binocular cues
depth cues, like retinal disparity, that depend on the use of both eyes
monocular cues
depth cues, like interposition and linear perspective, available to either eye alone
retinal disparity
a binocular cue for perceiving depth:by comparing images from urge retinas in the 2 eyes, the brain computes distance (the greater the difference between the 2 images, the closer the object
visual cliff
a lab device for testing depth perception in infants and young animals
depth perception
the ability to see objects in 3d although the images that strike the retina are 2d; allows us to judge distance
phi phenomenon
an illusion of movement created when 2 or more adjacent lights blink on and off in quick succession
clairvoyance
ability to see or know things without actually perceiving them via the senses.
parapsychology
the study of paranormal phenomena, including esp and psychokinesis
precognition
foreknowledge of an event
esp
perception can occur apart from sensory input; includes precognition, clairvoyance, and telepathy
telepathy
communication sent or received directly from one mind to another without using speech,
psychokinesis
can move objects by mental effort alone
interposition
an object is closer than the ones behind it because the closer object covers part of the farther object.
linear perspective
two identical items will appear to vary in size with the amount of distance involved and why roads appear to narrow with distance.
