AP Psych Unit 3
Sensation
Exploring through the sences
Perception
organizing and interpreting sensory information
Bottom-up processing
begins with the senses and works up (sensation)
Top-down processing
view things based on experience or expectations and work down
Selective attention
focusing on a particular stimulus (one TV at a time)
Cocktail party effect
focusing on one voice among many (type of selective attention)
Inattentional blindness
failing to see things because our attention is focused elsewhere
Change blindness
failing to notice changes in the environment (person giving directions)
Absolute threshold
the minimum stimulation needed to detect something 50 percent of the time (ex. Candle 30 miles away)—subliminal messages are below our absolute threshold
Difference threshold
the minimum it takes to detect difference between two things (also called just noticeable difference (jnd))
Weber’s law
things must differ by a percentage rather than an amount (quarter in shoe, candy bar)
Signal detection theory
detecting something based on experience, expectation, or motivation (ex. Baby’s cry, cell phone)
Sensory adaptation
diminished sensitivity to something (cold pool becomes warm)
Transduction
process of changing what we see into neural impulses
Cornea
protective covering
Pupil
opening in eye…where light enters
Iris
colored muscle around pupil…adjusts the light that enters eye
Lens
focuses images
Retina
contains rods and cones
Rods
see black and white
Cones
see color
Fovea
central focal point, where cones cluster
Bipolar Cells
Connect rods and cones to ganglion cells
Ganglion cells
Collect visual info and send to brain
Nearsightedness
can see close up, light focuses in front of retina
Farsightedness
can see far away, light focuses behind retina
Optic nerve
carries information from the eye to the brain
Blind spot
part where optic nerve leaves the eye…no cones or rods there
Feature detectors
respond to shape, angle and movement (Hubel and Wiesel)
Parallel processing
processing many things at once (color, motion, form…)
Young Helmholtz trichromatic theory
we have cones for red, green, and blue that mix to give all the combinations (subtractive is paint so it is black…additive is light and is white)
Opponent process theory
we have opposing pairs (red/green, yellow/blue, black/white) and when one wears out the other takes over (after image effect)
Audition
sense of hearing
Decibels
how we measure sound (0 is absolute threshold, above 85 can cause damage)
Outer ear
visible part (pinna) and auditory canal
Middle ear
three tiny bones (anvil, hammer, stirrup... aka ossicles
Inner ear (oval window)
contains cochlea, semicircular canals, and vestibular sacs
Cochlea
coiled, fluid filled tube in that triggers nerve impulses
Basilar membrane (middle of cochlea)
contains hair cells…fluid hits here
Place theory
depends on where the sound waves hit along the basilar membrane…best for high pitches
Frequency theory
the rate of impulses going up the auditory nerve matches the tone…better for low-pitched sounds
sound localization
we can locate sounds based on which ear they strike first
Conduction hearing loss
eardrum is punctured
Sensorineural hearing loss
damage to hair cells…comes from loud sounds or age (hearing aid or cochlear implant may help)
Taste (gustation) and smell (olfaction)
referred to as chemical senses
Olfactory bulbs
We smell with them
Sensory interaction
one sense influences another (smell and taste)
Skin senses
touch, pressure, temperature, pain
Kinesthetic sense
sensing and moving your body parts...knowing where your arm is
Receptors in muscles, tendons, and joints
Vestibular sense
body position and movement, our sense of balance
Receptors are located in the inner ear (semicircular canals and otolith organs)
Phantom limb sensations
sensations that come even when a limb is missing
Gate-control theory
The spinal cord contains a gate that either allows or blocks pain signals
Gestalt
an organized whole…the whole is greater than the sum of its parts (Gestalt Psychology)
Figure-ground
what you are looking at becomes your figure, the rest is the ground
Similarity
group things that are similar
Proximity
group things by how close together they are
Closure
fill in the gaps to make something look whole
Connectedness
group things by how connected they are
Continuity
we perceive smooth, continuous patterns
Size constancy
knowing the size of something doesn’t change (looking at homes from a plane)
Shape constancy
knowing that the shape doesn’t change
Lightness (color) constancy
knowing that something is the same color even when the lighting changes
Relative size
things that are closer look bigger
Interposition (overlap)
when one thing blocks another, it has to be closer
Texture gradient
the more detail something has, the closer it looks
Relative height
objects higher in the visual field look farther away
Relative clarity (aerial perspective)
distant objects are more hazy
Linear perspective
parallel lines seem to come together in the distance
Relative motion (motion parallax)
things below your field of vision look like they are moving backward and faster
Binocular cues
use two eyes (retinal disparity and convergence)
Retinal disparity (binocular disparity)
the difference in the images produced by your two eyes (retinal sausage)
Convergence
tendency for eyes to turn inward when looking at something close
Visual cliff
used to measure baby’s depth perception
Phi phenomenon
when lights turn on and off, it creates the sense of movement
Stroboscopic motion
“flip book”, looks like it creates movement
Perceptual set
a mental predisposition to perceive something one way or the other
Context effects
the context that we see something in alters our perception of it
Muller-Lyer illusion
we live in a perfectly carpentered world
Perceptual adaptation
we adapt to a changed visual input (basketball player with goggles)
ESP
extrasensory perception
Telepathy
mind to mind
Clairvoyance
perceiving remote events (thinking your house is on fire now)
Precognition
seeing future events (predicting 9/11)