AP PSYCH Unit 3

bottom-up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information

top-down processing

the use of preexisting knowledge to organize individual features into a unified whole

figure-ground relationship

The principle by which we organize the perceptual field into stimuli that stand out (figure) and those that are left over (ground).

gestalt rules

A set of rules that describe when elements in an image will appear to group together

proximity

objects that are close together are more likely to be perceived as belonging in the same group

similarity

the tendency to perceive things that look similar to each other as being part of the same group

continuity

the tendency to perceive things as simply as possible with a continuous pattern rather than with a complex, broken-up pattern

closure

objects that make up a recognizable image are more likely to be perceived as belonging in the same group even if the image contains gaps that the mind needs to fill in

constancy

our ability to maintain a constant perception of an object despite changes

size constancy

objects closer to our eyes will produce bigger images on our retinas, but we take distance into account in our estimations of size

shape constancy

Objects viewed from different angles will produce different shapes on our retinas, but we know the shape of an object remains constant.

brightness constancy

We perceive objects as being a constant color even as the light reflecting off the object changes.

stroboscopic effect

images in a series of still pictures presented at a certain speed will appear to be moving

phi phenomenon

an illusion of movement created when two or more adjacent lights blink on and off in quick succession

autokinetic effect

An optical illusion, in which a spot of light on a screen appears to move, when in actual fact it doesn't.

visual cliff

a lab device for testing depth perception in infants and young animals

monocular cues

depth cues that don't depend on having two eyes

binocular cues

depth cues that depend on the use of two eyes

linear perspective

A monocular cue for perceiving depth; the more parallel lines converge, the greater their perceived distance.

relative size cue

objects closer to the viewer are larger than the ones further away

interposition cue

objects that block the view to other objects must be closer to us

texture gradient

the tendency for textured surfaces to appear to become smaller and finer as distance from the viewer increases

binocular disparity

the difference in the retinal images of the two eyes that provides information about depth

extrasensory perception

the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition

sensation

the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

perception

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events

selective attention

the focusing of conscious awareness on a particular stimulus

inattentional blindness

failing to see visible objects when our attention is directed elsewhere

cocktail party effect

ability to attend to only one voice among many

change blindness

failing to notice changes in the environment

what is a by-product of what we are really good at: focusing attention on some part of the environment?

selective attention

choice blindness

failing to notice changes in the environment

popout

stimuli that draw our eye and demand our attention

transduction

conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brains can interpret.

psychophysics

the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them

absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time

signal detection theory

the minimum stimulation necessary to detect a particular light, sound, pressure, taste or odor 50% of the time

sublimial

below one's absolute threshold for conscious awareness

priming

An enhanced ability to think of a stimulus, such as a word or object, as a result of a recent exposure to the stimulus

difference threshold

the minimum difference between two stimuli required for detection 50 percent 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 adaption

diminished sensitivity as a consequence of constant stimulation

perceptual set

a mental predisposition to perceive one thing and not another

who found absolute threshold?

Gustav Fechner

who discovered feature detectors in our brain?

David Hubel and Torsten Wiesel

light intensity

how much energy light contains

light wavelengths

determines the particular hue we see

steps of vision

1. Light waves enter the cornea
2. Pass through the pupil
3. Pass through the lens
4. Projected onto the retina.
5. The rods and cones transduce the light waves into a neural impulse.
6. The neural impulses are sent to the optic nerve
7. The optic nerve carries messages from each eye to the primary visual cortex in the occipital lobe

cornea

a protective covering and helps the focus of light

accomodation

the process by which the eye's lens changes shape to focus near or far objects on the retina

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 and controls the size of the pupil opening

retina

the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information

lens

the transparent structure behind the pupil that changes shape to help focus images on the retina

cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.

rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond

fovea

an indention containing the highest concentration of cones

blindspot

the point at which the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there

optic chiasm

point at which optic nerve fibers cross in the brain

trichromatic theory

theory of color vision that proposes three types of cones: red, blue, and green

opponent-process theory

states that sensory receptors are arranged in the retina come in pairs

what are the pairs of colors?

red/green, blue/yellow, white/black

which theory explains color blindness?

opponent-process theory

which theory does not explain color blindness?

trichromatic theory

amplitude

Height of a wave

frequency

the number of complete wavelengths that pass a point in a given time

oval window

membrane at the enterance to the cochlea through which the ossicles transmit vibrations

eardrum

a thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate

choclea

a coiled bony fluid-filled tube in the inner ear trough which sound waves trigger nerve impulses

hammer

A tiny bone that passes vibrations from the eardrum to the anvil

anvil

A tiny bone that passes vibrations from the hammer to the stirrup

stirrup

A tiny U shaped bone that passes vibrations from the anvil to the cochlea.

organ of corti

Center part of the cochlea, containing hair cells, canals, and membranes

place theory

in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated

frequency theory

in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

gate-control theory

the theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain. The "gate" is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.

what 2 characteristics help determine our sensory experience?

wavelength and hue

parallel processing

the processing of many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision. Contrasts with the step-by-step (serial) processing of most computers and of conscious problem solving.

depth perception

the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance

motion perception

large objects appear to move slower than smaller objects

papillae

rough, bumpy elevations on dorsal surface of tongue

5 different tastes

sweet, sour, salty, bitter, umami

olfactory bulb

Gathers messages from the smell neurons and transmits them to the brain

what does our sense of smell depend on?

chemicals emitted by the substance

steps of smell

1) Odorants bind to receptors.
2) Olfactory receptor cells are activated and send electric signals.
3) The signals are relayed via converged axons.
4) The signals are transmitted to higher regions of the brain

vestibular sense

the sense of body movement and position, including the sense of balance

the vestinular sense has...

3 hairlike semicircular canals in the innear ear that give the brain feedback about body orientation

kinesthetic sense

sense of the location of body parts in relation to the ground and each other

what are the energy senses?

vision, hearing, touch

what are the chemical senses?

taste and smell

what are the body position senses?

vestibular sense, kinesthetic sense

audition

the sense or act of hearing

middle ear

the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window

inner ear

the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs

sensorineural hearing loss

hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea

cochlear implant

a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

how can the brain determine loudness?

by the number of activated hair cells

what does the place theory assume?

it assumes we hear different pitches caused by different sound waves traigger activity in different places along the cochlea's basilar membrane

which type of frequencies vibrate more in the membrane?

low frequencies