06. Sensation and Perception Flashcards
sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
sensory receptors
sensory nerve endings that respond to simuli
perception
the process by which our brain organizes and interprets sensory information
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; we construct perceptions drawing on our experience and expectations
transduction
conversion of one form of energy into another (ex. smell in our noses being interpreted by our brains)
psychophysics
the study of relationships between the physical characteristics of stimuli and our psychological experience of them
absolute threshold
minimum stimulus energy needed to detect a particular stimulus 50% of the time
signal detection
a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation
subliminal
below one’s absolute threshold for conscious awareness
difference threshold
the minimum difference between two stimuli required for detection 50% of the time
Weber’s law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)
sensory adaptation
diminished sensitivity as a consequence of constant stimulation
perceptual set
a mental predisposition to perceive one thing and not another
wavelength
the distance from the peak of one light or sound wave to the peak of the next
hue
the dimension of color that is determined by the wavelength of light
intensity
the amount of energy in a light wave or sound wave and is what we perceive as brightness or loudness (determined by the wave’s amplitude)
retina
the light-sensitive inner surface of the eye
accomodation
adapting our current schemas to incorporate new information; or the process by which the eye’s lens changes shape to focus near or far objects on teh retina
rods
retinal receptors that detect black, white, and gray, and are sensitive to movement
cones
retinal receptors that are concentrated near the center of the retina and that function in daylight or well-lit conditions; detects fine details and color sensations
optic nerve
the nerve 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 there are no receptor cells there
fovea
the central focal point in the retina, around which the eye’s cones cluster
three-colour theory
the theory that the retina contains three different types of colour receptors (red, green, blue)
opponent-process theory
the theory that opposing retinal processes (ex. white-black) enable colour vision
feature detectors
nerve cells in the brain’s visual cortex that respond to specific features of the stimulus (shape, angle, movement)
parallel processing
processing many aspects of a stimulus or problem simultaneously
gestalt
an organized whole
figure-ground
the organization of the visual field into objects that stand out from their surroundings
grouping
the perceptual tendency to organize stimuli into coherent groups
perceptual adaptation
the ability to adjust to changed sensory input, including an artificially displaced or even inverted visual field
perceptual constancy
perceiving objects as unchanging even as illumination and retinal images change
audition
the sense or act of hearing
middle ear
the chamber between the eardrum and cochlea containing three tiny bones - hammer, anvil, and stirrup
cochlea
a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses
inner ear
contains the cochlea, semicircular canals, and vestibular sacs
sensorineural hearing loss
caused by damage to the cochlea’s receptor cells or to the auditory nerve (nerve deafness)
conduction hearing loss
caused by damage to the mechanical system that conducts sound waves to the cochlea
cochlear implant
device for converting sounds into electrical signals stimulating the auditory nerve through electrodes threaded into the cochlea
place theory
the theory that links the pitch we hear 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 the tone, thus enabling us to sense its pitch
gate-control theory
the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain
hypnosis
a social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviours will spontaneously occur
gustation
sense of taste
olfaction
sense of smell
kinesthesia
our movement sense - our system for sensing the position and movement of individual body parts
vestibular sense
our balance sense - our sense of body movement and position that enables our sense of balance
sensory interaction
the principle that one sense can influence another, as when the smell of food influences its taste
embodied cognition
the influence of bodily sensations, gestures, and other states on cognitive preferences and judgements
extrasensory perception (ESP)
the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition
