ap psych - unit three study guide

sensation

how an organism receives stimuli and information from the surrounding world via sensory organs

perception

cognitive processes of receiving, encoding, storing, and organizing sensations

bottom-up processing

starts with sensory receptors and works up to the brain’s integration of sensory info for processing

\
ex: stubbing your toe

top-down processing

the construction of perceptions from sensations (coming from bottom-up) and on our own experiences/experiences

\
ex: if you’re in a bad mood and eating, the food might taste bad

psychophysics

study of the links between physical stimuli and psychological experience

absolute threshold

weakest amount of a stimulus that a person can detect 50% of the time

signal detection theory

ability to identify a stimulus (signal) when it is embedded in a distraction background

subliminal stimulation

stimulus which is below one’s threshold for conscious awareness

difference threshold

smallest difference between two stimuli which a person can detect 50% of the time or more

\
aka: just noticeable difference (jnd)

weber’s law

the principle that two stimuli must differ by a constant proportion, not a constant amount, for a difference between them to be connected

\
just noticeable difference (jnd)

\
about 2% for everything

transduction

conversion of one form of energy into another; receptor cells take incoming energy and change it into neural impulses

\
in hearing: cochlea

in vision: retina

in olfaction: cilia

in gustation: taste receptors

in touch: touch receptors

cocktail party effect

phenomenon of being able to focus one's auditory attention on a particular stimulus while filtering out a range of other stimuli, much the same way that a partygoer can focus on a single conversation in a noisy room

sensory adaptation

reduction in sensitivity a stimulus after constant exposure to it

\
physiological adaptation

\
self-regulated

habituation

kind of learning; nervous system selectively filters out stimuli

\
psychological adaptation - decreased response

\
conscious

selective attention

process of directing our awareness to relevant stimuli while ignoring irrelevant stimuli in the environment

wavelength

distance from the peak of one light/sound wave to the peak of the next

\
in light: color/hue

in sound: pitch

amplitude

top to bottom of a wave

\
in light: intensity

in sound: intensity/volume

pupil

adjustable opening in the center of the eye

iris

muscle that controls pupil size

lens

changes shape to help focus, accommodates

retina

light sensitive surface with rods and cones

\
rods and cones → bipolar cells → ganglion cells → optic nerve

acuity

sharpness of vision

nearsightedness/myopia

light focuses in front of the retina

\
objects near are clear and objects far are blurry

farsightedness/hyperopia

light focuses behind the retina

\
objects far are clear and objects near are blurry

\
much rarer

rods

periphery of retina

\
120 million

\
no color vision

\
sensitive to light and give twilight vision

cones

clustered in the fovea

\
fewer than rod cells (6-7 million)

\
center of the retina

\
color and daylight vision

optic nerve

carries neural impulses to the thalamus

blind spot

where optic nerve leaves the eyeball

blindsight

condition in which a person can respond to a visual stimulis without consciously experiencing it

fovea

center focus point

malleus

another name for hammer

\
^^a small bone in the middle ear that transmits vibrations of the eardrum to the incus (anvil)^^

incus

another name for anvil

\
^^a small anvil-shaped bone in the middle ear, transmitting vibrations between the malleus (hammer) and stapes (stirrup)^^

stapes

another name for stirrup

\
^^a tiny, U shaped bone that passes vibrations from the anvil (incus) to the cochlea^^

stroop effect

\n brains recognize color first, interfering with our ability to read aloud

\
need selective attention to identify the color of the word

feature detectors

respond to visual aspects of the environment (shape, angle, movement)

\
visual cortex

\
send information to neural networks (supercell clusters) that can perform tasks like visualizing faces

\
cube, triangle (gestalt)

parallel processing

brain processes many aspects simultaneously

\
divides a visual scene into sub-dimensions

young-holtzman trichromatic theory

retina has three receptors sensitive to red, green, and blue

opponent-process theory

opposing retinal processes enable color vision

\
red and green, blue and yellow, white and black

color constancy

\n perceiving familiar objects as having consistent color under different conditions of illumination

\
ex: black and blue or white and gold dress

audition

sense/act of hearing

frequency theory

rate of nerve impulses travelling up the auditory nerve matches the frequency of a tone, enabling us to sense its pitch

\
^^explains how we sense low pitches^^

place theory

\n links the pitch we hear with the place where the cochlea's membrane is stimulated

\
^^explains how we sense high pitches^^

pinna

external part of the ear

auditory canal

tube that runs from outer ear to middle

eardrum

tympanic membrane that vibrates with sound waves

\
middle ear

hammer, anvil, sitrrup

smallest bones; vibrate from the eardrum

\
middle ear

cochlea

where transduction occurs

\
coiled, bony, fluid-filled tube where sound waves trigger neural impulses

\
filled with hair cells

\
inner ear

semicircular canals

fluid filled tubes to help keep balance; connect to vestibular sacs

\
inner ear

basilar membrane

a fibrous membrane within the cochlea that supports the organ of corti

synesthesia

to perceive together; perceptual phenomenon in which stimulation of one sensory or cognitive pathway leads to involuntary experiences in a second cognitive or sensory pathway

conduction hearing loss

damage to the system that conducts sound waves to the cochlea

\
most likely due to a punctured eardrum

sensorineural hearing loss

damage to the cochlea’s receptor cells or to the auditory nerves

gate-control theory

neurological “gate” in the spinal cord which opens to allow small fibers of pain through but large fibers can override small fibers to stop pain

\
a-delta fibers: small myelination; sharp, immediate pain

c-fibers: dull, aching pain (chronic)

beta fibers: sense touch

sensory interaction

experiences result in two or more senses working together because one sense can influence another

kinesthesis

system for sensing the position and movement of individual body parts

\
aka: proprioception

vestibular

sense of body movement, position, and spatial orientation; including sense of balance

\
located in the semicircular canal

gustation

taste, chemical sense

\
5 basic sensations:

sweet - energy source

salty - sodium essential to psychological processes

sour - potentially toxic acid

bitter - potential poisons

umami - proteins to grow and repair tissue

fungiform papillae

swellings on the anterior surface (front) of the tongue, in humans numbering about 200 and each shaped like a mushroom

\
taste buds

\
decrease with age

taste process

1. molecules enter taste pores of taste buds and stimulate taste cells
2. nerve impulses travel via the facial/glossopharyngeal nerve to the brain
3. impulse reaches the thalamus, where it is rerouted to the temporal lobe
4. taste stimuli is processed by the gustatory cortex

olfaction

smell, chemical sense

\
odorants enter the nasal cavity to stimulate five million receptors in the mucous membranes

phermones

chemical message sent by a chemical

smell process

1. olfactory receptors
2. olfactory bulb (below frontal lobe)
3. olfactory areas in the temporal lobe
4. limbic system

\
hippocampus and amygdala can create strong emotional responses and memories associated to smell

nociceptors

sensory receptors that detect pain

pain → brain process

1. nociceptors
2. nerve fibers

inattentional blindness

selectively attending to one part of the environment and missing another

change blindness

specific form of inattentional blindness

\
fail to notice changes in our environment

prosopagnosia

neurological disorder characterized by the inability to recognize faces

gestalt

an organized whole, tendency to integrate meaningful pieces of info into meaningful wholes

figure-ground

organization of the visual field onto objects that stand out from their surroundings

grouping

after distinguishing the figure from the ground, our perception needs to organize the figure into a meaningful form using grouping rules (proximity, similarity, continuity, closure, and connectedness)

convergence

neuromuscular cue to tell brain the closeness of an object

\
binocular

retinal disparity

difference between how each retina experiences the world

\
binocular

relative height

vertical dimensions seem longer than identical horizontal

\
monocular

relative size

allows you to determine how close objects are to an object of known size

\
monocular

relative motion (parallax)

as we’re moving, objects that are actually stable seem to move

\
monocular

interposition

if one object partially blocks our view of another, we percevie it as closer

\
monocular

relative clarity

hazy/blurry objects seem farther away than sharp, clear ones

\
monocular

texture gradient

gradual change from coarse, distinct texture to a fine, indistinct texture signals increasing distances

\
monocular

linear perspective

as lines converge, greater distance is perceived

\
monnocular

light/shadows

using light and shadows to perceive depth

\
monocular

stroboscopic movement

the apparent motion of a series of separate stimuli occurring in close consecutive order, as in motion pictures

depth perception

ability to see objects in 3d although the images that strike the retina are 2d

ponzo effet

visual illusion in which the upper of two parallel horizontal lines of equal length appears to be longer than the bottom of the two lines when they are flanked by oblique lines that are closer together at the top than they are at the bottom

distal stimuli

stimuli that lie outside of the body

proximal stimuli

stimulus energies that impinge directly on our sensory receptors

muller-lyer illusion

optical illusion in which two lines of the same length appear to be of different lengths

ames room illusion

an irregularly shaped but apparently rectangular room in which cues for depth perception are used experimentally to distort the viewer's perception of the relative size of objects within the room

lightness constancy

perceiving objects with the same level of brightness, even though the illumination may change

perceptual adaptation

adjust to artificially displaced or even inverted visual field

perceptual set

mental predisposition to perceive one thing and not another

mcgurk effect

occurs when a person perceives that another's lip movements do not correspond to what that individual is saying

gustav fechner

coined the term “absolute threshold”

david hubel

demonstrated that neurons in the occipital lobe's visual cortex receive information from individual ganglion cells in the retina (feature detector cells)

\
also proved that the brain divides a visual scene into several subdimensions (color, movement, etc.) and processes each separately

ernst weber

created “weber’s law”

daniel kahneman

conducted research to discover factors that influence human judgment and decision making

torsten wiesel

discovered feature detectors