Unit 3: Sensation and Perception Flashcards
Sensation
process by which sensory receptors and nervous system receive and represent stimulus energies
perception
the process of organizing/interpreting this information
sensory receptors
nerves that respond to stimuli
bottom-up processing
starts with your sensory receptors and work up to the higher levels of processing
top-down processing
constructs perception from sensory input by drawing on experience and expectations
selective attention
focus of conscious awareness on a particular stimulus
inattentional blindness
failing to see visible objects when attention is directed elsewhere
transduction
conversion of one form of energy into another form that the brain uses
psychophysics
study of relationships b/w the physical characteristics of stimuli, such as the intensity and psychological experience of them
subliminal
below one’s absolute threshold for conscious awareness
perceptual set
a mental predisposition to perceive one thing and not the others
extrasensory perception (ESP)
external source by which some people derive perception, that is not sensation, cognition or emotion
(telepathy, clairvoyance, precognition)
parapsychology
study of paranormal phenomena including ESP and psychokinesis
rods
one kind of receptor cell concentrated at the edges of the retina
is key to peripheral and twilight vision: detects black/white/gray and is movement sensitive
cones
one kind of receptor cell concentrated at the center of the retina
key to color sensation:
function in well-lit conditions and detect detail
cornea
clear protective outer layer that covers pupil and iris
pupil
adjustable opening in the center
iris
colored part of the eye
retina
multilayered sensitive inner surface of the eyeball
accomodation
process by which lens changes shape to help focus
optic nerve
carries neural impulses from eye to brain
blind spot
where the optic nerve leaves the eye and there are no receptors
fovea
where cones cluster around, the central focal point of retina
Young-Helmholtz Trichromatric (3 color) theory
retina contains three different types of color receptors (red/green/blue) which when stimulated in combination produce the perception of any color
opponent-process theory
opposing retinal processes(red-green/blue-yellow/white-black)
feature detectors
nerve cells in the visual cortex that respond to specific features of the stimulus(shape, angle, movement)
parallel detectors
processing many aspects of a problem simultaneously
(default information processing for brain)
gestalt
whole/form
figure-ground
distinction of the figure form its surrounding in the visual field
grouping principles (there’s 3)
proximity: group nearby figures together
continuity: perceive smooth continuous patterns
closure: fill the gaps to create complete objects
depth perception
ability to see 3D although images that strike the retina and 2D; enables us to judge distance (ex: video game environments)
binocular cues
depth cue that depends on use of both eyes
retinal disparity
due to the distance between the eyes, we perceive two different images, the more different these two images are, the closer the object is to us
monocular cues
depth cue available to either eye alone
phi phenomenon
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, color, brightness, shape, and size) even when illumination/retinal images change (a top-down process)
color constancy
perceiving familiar objects as having consistent color even if illumination changes
perceptual adaptation
ability to adjust to changed sensory inout, including an artificially displaced or even inverted visual field
audition
sense or act of hearing
frequency
determines the pitch(high/low tone)
eardrum
first to receive sound vibration
middle ear
second part, piston made of 3 tiny bones
bones of middle ear
hammer, anvil, stirrup
cochlea
bony, fluid-filled tube which triggers nerve impulses; located in the inner ear
oval window
cochlea’s membrane-covered opening; vibrated by the cochlea which jostles the fluid inside
basilar membrane + hair cells
membrane that bends the hair cells that line its surface, triggering impulses in adjacent nerve cells
auditory nerve
formed by the converging axons of nerve cells
a nerve connecting the inner ear with the brain and carrying nerve impulses concerned with hearing and balance
sensorineural hearing loss
nerve deafness caused by damage to the cochlea’s hair cell receptors
conduction hearing loss
a less common form of hearing loss, caused by damage to the mechanical system that conducts sound waves to the cochlea (hearing can only be restored by a cochlear implant)
Place theory
we perceive sound waves with different pitches because they trigger activity at different places along the cochlea’s basilar membrane
(high frequency produces large vibrations near the beginning of the membrane /low frequencies vibrate more but unclear where which is a key issue w/ the theory)
overall helps explain high frequency hearing
frequency/temporal theory
brain reads pitch by monitoring frequency of neural impulses traveling to the auditory nerve
(issue w/ theory is that individual neurons can’t fire faster than 100x per sec, however we can sense sounds with frequencies of 100x waves per second)
overall helps explain low pitch hearing
Gate control theory
the spinal cord contains a neurological gate that blocks pain signals or allows them access to the brain
is opened by activity of pain signals traveling up smaller nerve fibers and is closed by activity in large fibers or by brain messages
(when tissue is injured you feel pain, yet acupunctures trigger no pain)
kinesthesia
our sense of movement and position
sensory interaction
senses influence each other and our brain blends the information to form perception
vestibular sense
our sense of our movement and position that enables balance; differs from kinesthesia in that it emphasizes movement in relation to gravity and the environment
nociceptors
sensory receptor for painful stimuli
semicircular canals
three tiny, fluid-filled tubes in the inner ear that help you keep your balanc
olfactory bulb
a neural structure of the vertebrate forebrain involved in olfaction, the sense of smell
absolute threshold
a neural structure of the vertebrate forebrain involved in olfaction, the sense of smell
difference threshold
a neural structure of the vertebrate forebrain involved in olfaction, the sense of smell
