Unit 3 Vocab - Sensation Flashcards
sensation
the faculty through which the external world is apprehended
occurs when the sensory nerves are activated by a stimuli
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 info
top-down processing
info processing guided by higher-level mental processes, as when we construct perceptions drawing on our experiences and expectations
psychophysics
the physical relationship between the physical characteristics of stimuli (intensity), and our physcal experience of them
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50% of the time
signal detection theory
theory predicting how and when we detect the prescence of a faint stimulus amid background stimulation
assumes no single absolute threshold and detection depends on the person
subliminal
below one’s absolute threshold for conscious awareness
priming
the activation, often unconsciously, of particular associations - predisposes perception, memory, and response
difference threshold (Just Noticeable Difference)
the minimum difference between 2 stimuli required for detection 50% of the time
Weber’s Law
the principle that, for 2 stimuli to be perceived as different they must differ by a constant minimum percentage, not a constant amount
sensory adaptation
diminished sensitivity as a consequence of constant stimulation
transduction
conversion of one form of energy into another
the transforming of stimuli into neural impulses
wavelength
the distance between crests of waves
hue
the dimension of color that is determined by the wavelength of light waves
intensity
the amount of energy in a light/sound wave
determines brightness/loudness as determined by the amplitude of a wave
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, controls the size of the pupil
lens
transparent structure behind the pupil that changes shape to help focus images on the retina
accommodation
adapting our current understandings to incorporate new info
retina
light sensitive inner surface of he eye
contains receptor rods and cones + layers of neurons that begin the processing of visual info
acuity
sharpness or keenness of vision/hearing/etc.
nearsightedness
nearby objects are seen more clearly than distant objects because the eye is elongated
farsightedness
faraway objects are seen more clearly than near objects because the eye is shortened
rods
retinal receptors that detect white/black/gray
necessary for peripheral and twilight vision when cones don’t respond
cones
retinal receptor cells that are connected near the center of the retina
function in daylight/well-lit conditions
detect fine detail and give rise to color sensations
optic nerve
nerve at the back of the eye that carries neural impulses from the eye to the brain
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 where the cones of the eye cluster
feature detectors
nerve cells in the brain that respond to specific features of the stimulus (shape, angle, movement)
parallel processing
processing many aspects of a problem simultaneously
it is the brain’s natural mode of info processing for many functions
Young-Helmholtz Trichromatic Theory
retina contains 3 different color receptors - blue, green, red
opponent process theory
theory opposing retinal processes (red-green, yellow-blue, white-black) enable color vision
ex. some cells are stimulated by green and inhibit red, and 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 waves that pass a given point in a certain amount of time
pitch
a tone’s highness/lowness
depends on frequency
middle ear
the chamber between the eardrum and the cochlea
contains 3 bones - hammer, anvil, and stirrup, that concentrate the vibrations of the eardrum on the cochlea’s oval window
cochlea
the fluid-filled, coiled tunnel in the inner ear that contains the receptors for hearing
inner ear
structures and liquids that relay sound waves to the auditory nerve fibers on a path to the brain for interpretation of sound
place theory
the theory that the pitch we hear is linked with the place where the cochlea’s membrane is stimulated
frequency theory
the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of tone which enables us to sense its pitch
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea
sensorieneural hearing loss
hearing impairment caused by lesions or dysfunction of the cochlea or auditory nerve
cochlear implant
device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
gate-control theory
theory that the spinal cord contains a neurological gate that blocks pain signals or allows them to pass
gate opened by activity of pain going up small nerve fibers, closed by large fibers/info coming from brain
sensory interaction
principle that one sense may influence another
ex. when smell influences taste of food
kinesthesis
the system for sensing the position and movement of individual body parts
vestibular sense
sensoery structure located in structures of the inner ear that registers the orientation of the head
