Sensation and Perception Flashcards
transduction
the process in which signals are transformed into neural impulses
cocktail-party phenomenon
when your attention involuntarily switches (someone calls your name)
cornea
a protective covering of the eye
pupil
dilates and becomes smaller to allow the right amount of light into your eye
lens
curved and flexible in order to focus the light
retina
a screen on the back of your eye
cones
cells activated by color
rods
cells that respond to black and white
fovea
located at the center of your retina and contains the highest concentration of cones
ganglion cells
their axons make up the optic nerve that sends visual impulses to the lateral geniculate nucleus in the thalamus
lateral geniculate nucleus
a place in the thalamus that receives impulses from the optic nerve
blind spot
where the optic nerve leaves the retina, calls such because has no rods or cones
optic chasm
the place nerves from both eyes join and cross over within the brain
feature detectors
discovered by Hubel and Weisel, nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement
trichromatic theory
there are three types of cones in the retina (blue, red and green) that activate in different combinations to produce all the colors of the visible spectrum
afterimage
an image (usually a negative image) that persists after stimulation has ceased
opponent-process theory
the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green
amplitude
the height of a sound wave, measured in decibels
frequency
the length of the waves and determines pitch, measured in megahertz
order of sound in your ear
ear canal -> eardrum/tympanic membrane -> hammer (malleus bone) -> anvil (incus bone) -> stirrup (stapes bone) -> oval window -> cochlea (snail’s shell filled with fluid) -> hair at bottom of cochlea -> organ of Corti (neurons activated by the hair) -> auditory nerve
place theory
hair cells in the cochlea respond to different frequencies of sound based on where they are located in the cochlea
frequency theory
place theory works for high frequency sounds, but not low frequency
conduction deafness
something goes wrong with the system of conducting sound to the cochlea
nerve (sensorineural) deafness
when the hair cells in the cochlea are damaged, usually by loud noise
gate-control theory
when a higher priority pain message coincides with a lower priority pain message, only the higher one will be felt
papillae
the bumps on your tongue
olfactory bulb
one of two enlargements at the terminus of the olfactory nerve at the base of the brain just above the nasal cavities
vestibular sense
how our body is oriented in space
kinesthetic sense
the position and orientation of specific body parts
absolute threshold
the smallest amount of stimulus we can detect
subliminal
stimuli below absolute threshold
difference threshold (just-noticeable difference)
the smallest amount of change needed in a stimulus before we can detect a change
Weber’s law
the change needed to make a noticeable difference to something is proportional to the original intensity of the stimulus
signal detection theory
a theory predicting how and when we detect the presence of a faint stimulus (“signal”) amid background stimulation (“noise”). Assumes there is no single absolute threshold and detection depends partly on a person’s experience, expectations, motivation, and level of fatigue.
response criteria (receiver operating characteristics)
how motivated people are to detect certain stimuli and expectations for what they want to perceive
false positive
when we think we perceive a stimulus that is not there
a false negative
not perceiving a stimulus that is present
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions
schemata
mental representations of how we expect the world to be
perceptual set
a predisposition to perceiving something in a certain way
backmasking
supposed hidden messages musicians recorded backward in their music
bottom-up processing (feature analysis)
we use only the features of the object itself to perceive it
figure-ground relationship
A Gestalt principle of perceptual organization that states that we automatically separate the elements of a perception into the feature that clearly stands out and its less distinct background.
constancy
the ability to maintain a constant perception of an object despite changes in direct appearance
visual cliff experiment
created by E.J. Gibson, used to determine when infants can perceive depth
Muller-Lyer illusion
demonstrates that some perceptual rules are learned from culture
Weber’s law for sight
constant for vision: 8%
Weber’s law for hearing
constant for hearing: 5%
forebrain
controls thought and reason
thalamus
part of forebrain
hypothalamus
part of forebrain
amygdala and hippocampus
hippocampus- arms surrounding the thalamus
limbic system
made up of thalamus, hypothalamus, amygdala and hippocampus
fissures
wrinkles in the cerebral cortex
contralateral control
each hemisphere of the brain controls the opposite side of the body
brain lateralization/hemispheric specialization
specialization of function in each hemisphere
corpus callosum
the nerve bundle that connects the two hempisheres; cut in split-brain patients
split-brain patients
patients whose corpus callosums have been cut
association area
any area of the cerebral cortex that is not associated with receiving sensory information or controlling muscle movements
frontal lobes
part of the cerebral cortex
Broca’s area
in the frontal lobe
motor cortex
in the frontal lobe
parietal lobes
contains sensory cortex (somato-sensory cortex)
sensory cortex (somato-sensory cortex)
receives incoming touch sensations from the rest of the body
occipital lobes
at the very back of the brain
temporal lobes
unlike occipital lobes, sound from either ear is processed in both temporal lobes
Wernicke’s area
located in temporal lobe
brain plasticity
the ability of other parts of the brain to take over functions of damaged regions. Declines as hemispheres of the cerebral cortex lateralize.
adrenal glands
produce adrenaline, which causes rest of body to go into fight or flight mode
Thomas Bouchard
conducted study on identical twins that found a correlation of 0.69 on IQ, criticized because their similar appearances may have led to their being treated similarly
Turner’s syndrome
only one X chromosome in the 23rd pair
Klinefelter’s syndrome
extra X chromosome
Down’s syndrome
extra chromosome on the 21st pair
