AP Psych Unit 4 Sensation and Perception

cornea

eye’s clear protective outer layer

iris

forms colored portion of eye; controls size of the pupil opening

pupil

opening of eye through which light enters

lens

changes its shape to help focus images on the retina; sends images upside down and visual cortex makes it right side up

fovea

depression in the retina of the eye where visual acuity is highest

retina

contains rods, cones, and layers of neurons that process visual information (fovea is inside this place)

photoreceptors

where transduction occurs in vision; rods and cones

rods

tinted yellow; 100 million in eyes and function in dim light; dictate black and white not colors and is needed for peripheral and twilight vision

cones

near retina center; 6 million near fovea and function in bright and daylight; detect fine detail and enable color perception; tinted purple

ganglion cells

form optic nerve fiber; receive visual signals from the bipolar cells and send that info to the brain

bipolar cells

receive visual signals from the rods/cones and pass them on to the ganglion cells

optic nerve

transmits visual information from the retina to the brain

blind spot

point of exit for ganglion cell axons (no photoreceptors here); also called optic disk

transduction

transformation of stimulus energy into a neural impulse ,like rods/cones being able to detect light waves (occurs in retina)

brightness

determined by amplitude and related to perceived intensity; also called intensity

color

dimension of color determined by length of wavelength of light; also called hue; short wavelength = bluish hue and long wavelength = reddish hue

trichromatic theory

suggests that retina (cones) contain three receptors sensitive to red, green, and blue colors; also called young-hemholtz theory

opponent process

theory proposed by Hering that we process four primary colors opposed in pairs of red-green, blue-yellow, and black-white; creates after images

after image

an image that remains after the stimulation to the retina has ended (colors you see that aren’t actually there in the image)

color blind

prevents from discriminating between certain colors due to a weakness in one of the cones (deficiency); most common distinguishing between red and green

inattentional blindness

failure to see objects in visual field when attention is directed elsewhere

change blindness

failure to notice changes over time in the environment (whodunnit video)

pinna

visible outer ear on either side of your head; helps pinpoint and locate sound

ear canal

where sound travels to reach eardrum

tympanic membrane

ear drum; vibrate at a rate that corresponds to the sound’s frequency transmits to ossicles

ossicles

three bones, the hammer, anvil, and stirrup, that pick up eardrum vibrations, amplify them, and pass them along to the cochlea in the inner ear

semicircular canals

fluid filled channels that help maintain balance

cochlea

a coiled-fluid filled tube through which sound waves are transduced into nerve impulses

external ear

contains the pinna and ear canal

middle ear

contains the ear drum (tympanic membrane) and ossicles (hammer, anvil, stirrup)

inner ear

contains the semicircular canals and cochlea

place theory

sound frequencies stimulate basilar membrane on specific hair cells (places) resulting in perceived pitch

hair cells, high frequency

loss of ____ as you age = less ability to hear _____ sounds

frequency theory

nerve impulses traveling in auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

auditory localization

brain determining the location of sound depending on ear

mcgurk effect

interaction of vision and hearing; auditory component + visual component of another sound = new sound

basilar membrane

a strip of tissue in the cochlea that vibrates when sound waves move in the cochlea fluid; has hair cells that bend to turn the vibrations into neural impulses sent to brain

conductive deafness

problem transferring sound waves anywhere along the route through the outer or middle ear; effects middle ear and hearing aids are used to help

sensorineural deafness

damage to the inner ear (cochlea/hair cells) that can be by excessive loud sounds, earbuds, and concerts; affects inner ear and cochlear implants help

sensation

process in which our sensory receptors receive information from our environment; data coming in

perception

process of organizing and interpreting sensory information into meaningful objects/events; how we interpret data

energy

detect a type of energy that gives information about the environment; sight, touch, hearing

chemical

providing information about the chemical composition of substances; taste, smell

kinesthetic

body position sense that gives feedback about position and orientation of specific body parts

vestibular

body position sense that tells us how our head (body) is oriented in space; influences balance and semicircular canals cause it

bottom up processing

analysis that begins with sensory receptors and works up to sensory information

sensory reception

part 1 in bottom up processing; taste

form an interpretation

part 2 in bottom up processing; yum

top down processing

perception based off previous events; previous experience and expectations affect the detection and analysis of information from the senses; explains visual illusions

signal detection theory

predicts how and when a person detects a signal; how intense (loud) a noise is and how alert you are

psychophysics

methods that measure the strength of a stimulus and the observer’s sensitivity to the stimulus

absolute threshold

minimum stimulation needed to register an external stimulus 50% of the time (can you hear? can you feel?)

difference threshold

minimal change in a stimulus that can just barely be detected (just noticeable difference/JND)

Weber’s Law

the size of the JND is a constant proportion of the size of the initial stimulus; percent change matters to JND, not amount

prosopagnosia

neurological condition characterizes by the inability to recognize the faces of familiar people

extra sensory perception

perception without sensory input

perceptual set

a mental predisposition to perceive one thing and not another

cocktail party effect

ability to filter out all stimuli except what is important to us

context effect

the influence of the surrounding environment or situation on a person’s perception

sensory adaptation

diminished activity over constant stimulation; not feeling a watch after some time of wearing it

perceptual adaptation

adjustments of how we adapt to environment and filter out distractions; image is inverted when eye sees it and the brain reverts it

perceptual constancy

our perception that objects don’t change

color perception

our ability to perceive an object as the same color regardless of the environment

size perception

objects remain same size regardless of distance

gestalt grouping

the perceptual tendency to organize stimuli into coherent groups

figure ground

perceive objects (figures) as distinct from their background (ground)

proximity

perceive objects as belonging together when they are close to one another

similarity

group objects that have similar characteristics

closure

group disconnected pieces of information into a meaningful whole; we fill in the image

apparent movement

a perceptual illusion where the brain perceives movement in stationary objects or a sequence of static images

motion perception

the brain's process of detecting, tracking, and interpreting the movement of objects and self-motion in the environment

phi phenomenon

the illusion of movement created by presenting visual stimuli in rapid succession

binocular cues

information taken in by both eyes

monocular cues

cues to help us perceive depth without a need of using both eyes

depth perception

ability to gauge length, width, and depth and to judge how far away an object is

visual cliff

suggests that human infants (crawling age) learn depth perception

ponzo illusion linear

lines that seem to converge in an image

relative clarity

nearby objects are clearer than more distant objects

relative height

near objects are low in visual field; more distant are higher up

texture gradient

texture of objects appears to change with distance

relative size

an object that appears larger than another object believed to be of the same size is judged to be closer

interposition

objects that are obscured by other objects and are perceived as being farther away

accommodation

The process by which the lens changes shape so as to focus the image of an object on the retina

retinal disparity

When we stare at an object, each eye receives a slightly different image, providing a depth cue known as

gestalt psychology

The tendency for our brain to perceive things as an organized whole rather than individual separate parts.

sensory interaction

The idea that information from one sense may influence another, as in the case of taste and smell, is called what?