ap pysch modules 20-25

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 stimuli

perception

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

bottom-up processing

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

top-down processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations

selective attention

the focusing of conscious awareness on a particular stimulus

cocktail party effect

ability to attend to only one voice in a sea of other voices

divided attention

the ability to carry out multiple tasks at once; interfere if overlapping

inattentional blindness

failing to see visible objects when our attention is directed elsewhere

change blindness

failing to notice alterations in our environment, ex: choice blindness

transduction

conversion of one form of energy into another

Psychophysics

the study of relationships between the physical properties of stimuli and our psychological experience

absolute threshold

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

signal detection theory

a theory predicting how and when we detect the presence of a faint stimulus amid background stimulation

4 reasons for signal detection theory

experience, expectations, motivation, and alertness

subliminal

below one's absolute threshold for conscious awareness

priming

the activation, often unconsciously, of certain associations, predisposing one's perception, memory, or response

difference threshold

the minimum difference between two stimuli required for detection 50 percent of the time

webers law

the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage

sensory adaptation

diminished sensitivity as a consequence of constant stimulation

perceptual set (ps)

a mental predisposition to perceive one thing and not another

ps context effects

stimuli affected by whats around it

ps motivation

motivation changes from one thing after seeing another

ps emotion

feelings about the world make you see your emotions everywhere

esp

extrasensory perception; the claim that perception can occur apart from sensation

telepathy

mind to mind communication

clairvoyance

the ability to see remote events

precognition

the ability to predict the future

parapsychology

the study of paranormal phenomena

Wavelength

the distance from peak to peak of a wave; determines color in lightwaves

hue

the dimension of color that is determined by wavelength; red, blue, green, magenta, yellow, cyan

intensity

the amount of energy in a wave as determined by the waves amplitude (height)

cornea

a clear protective layer that covers the iris and pupil

aqueous humor

a gel layer between the iris and pupil

pupil

the adjustable opening in the center of the eye through which light enters

iris

a ring shaped colored muscle that controls the size of the pupils opening

lens

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

accomodation

the process by which the eye's lens changes shape to focus on images near and far

retina

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

rods

receptors in the retina that detect gray scale and movement and provide peripheral and twilight vision

cones

receptors in the retina that detect fine detail and color in daylight or well-lit conditions

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 spot with no retinal receptors

fovea

the focal point in the retina around which the eyes cones cluster

feature detectors

nerve cells in the brain's visual cortex that respond to specific features of a stimulus, such as shape, angle, or movement

Young-Helmholtz trichromatic theory

the theory that the retina contains three different color receptors; red, green and blue, which, when stimulated in combination, can produce the perception of any color.

opponent-process theory

the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision

gestalt

an organized whole; necker/impossible cube

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

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

visual cliff

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

binocular cues

depth cues that use both eyes

retinal disparity

by comparing retinal images from each eye the brain can judge distance

monocular cues

depth cues using one eye

Interposition

objects that are partially blocked are perceived as farther away than complete objects

relative height

we perceive objects higher in our field of vision as farther away

relative motion (motion parallax)

As we move, objects that are actually stable may appear to move; close objects appear to move backwards, objects in the distance appear to move slowly with us

relative size

assuming objects are similar in size, the object that is larger is perceived to be closer

linear perspective

parallel lines appear to converge with distance; the sharper the angle of convergence, the greater the perceived distance

lights and shadows

shading produces a sense of dept, consistent with our assumption that light comes from above

phi phenomenon

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

perceptual constancy

perceiving objects as unchanging even as sensation changes

shape constancy

perceiving the shape of an object as unchanging even as retinal images of the shape change

color constancy

perceiving the color of an object as unchanging even as retinal images of the color change

brightness constancy

perceiving an object as having unchanging brightness even as reflective wavelengths of light alter

ames room

an optical illusion

perceptual adaptation

the ability to adjust to changing sensory input

audition

the sense or act of hearing

frequency

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

pitch

a tones perceived highness or lowness as determined by frequency

timbre

the quality or a sound distinct from its pitch and loudness

outer ear

the ear cartilage and ear canal; funnels soundwaves towards the middle ear and inner ear

middle ear

ear drum(tympanic membrane), malleus (the hammer) the incus (anvail, stirrup) function- helps concentrate vibrations of the ear drum on the cochleas oval window

inner ear

contains the cochlea, semi circular canals, and the vestibular sacs; processing sound begins

conductive/conduction hearing loss

hearing loss caused by damage to the mechanical systems that conduct sound waves to the cochlea

sensory neural hearing loss

caused by damage to the cochleas receptor cells or auditory nerve

cochlea

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

cochlear implant

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

perception of sound (timbre)

frequency determines pitch, amplitude determines loudness or volume (dB decibels)

place theory (basilar membrane)

the theory that links the pitch we hear with the spot where the cochleas basilar membrane is stimulated (high frequencies not low)

frequency theory

the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone (low frequencies not high)

volley principle

the theory that the nerve impulses of the auditory nerve are combined

touch

a sensation within your skin

temperature

thermal receptors adapt to temp easily

sense of pressure

2 levels of pressure; meissner corpuscule- light pressure, pacinion corpuscule- hard pressure

pain

nociceptors

gate control theory of pain

the theory that the spinal cord contains a neurological gate that either blocks pain signals or allows that to travel to the brain

phantom limb syndrome

when people who are lacking limbs continue to report sensations in those limbs

social-critical incfluences on pain

what pain are we allowed to feel

gustation

sense of taste

sweet

detects energy sources

salty

good for physiological functions

sour

detects potentially toxic acids

bitter

detects potential poisons

umami

detects proteins

olfaction

sense of smell; olfactory bulb- concentration of olfactory nerves above the nose

kinesthesia

our sense of movement and body position

vestibular sense

sense of body position and balance

sensory interaction

the principle that one sense may depend on another