PSYC Chapter 5; Test 1

Ch 5

sensation

the detection of physical stimuli and transmission of that into the brain through the PNS

perception

making sense of what you’re sensing

receptors

notice stuff in the environment, receives details from outside world; need one for every sense

transduction

the conversion of that energy to action potential (the only energy the brain understands

adaptation

all senses do this; a reduced sensitivity to a constant stimulus

absolute threshold

there’s a minimum amount of energy in your environment that you can perceive; What’s the least amount of light you can see in a pitch-black room? Faint smells that you can’t smell

difference threshold

the minimum difference between TWO things that you can reliably perceive; if you are holding 2 tissue boxes and one of them only has one less tissue, you likely won’t be able to tell the difference

bottom-up processing

sensation processing; raw data collection; not knowing an apple and being told/shown what it is

top-down processing

interpreting based on experience; knowing an apple is an apple because you’ve seen/heard about it before

smell

which sense is the only one that doesn’t pass through the thalamus to get information to the brain?

pupil

the black circle in the iris; gets bigger in a dark room, smaller in bright room to accommodate for light receptors—gets more/less covered, this isn’t the thing changing size

iris

what determines the color of your eyes

sclera

the white of the eye; strong, rubbery material; helps you perceive the world, keeps eyeball as an eyeball, holds structure

cornea

outer surface of the eye; where you put contact lenses/get scratchesl

lens

changes shape all the time to focus on images that are far away/close up; the reason why people might need glasses

retina

in the back of the eyeball, where the receptors for vision are; covers the entire back surface of the eye

rods

some of the receptors for vision in the retina; monochromatic; detects light; sensitive to light and motion

cones

the other receptors for vision in the retina; dominate the fovea of the retina; allows for color vision; good for fine detailed vision;

ganglion cells

what the rods and cones send a message to; these send messages to the thalamus that sends it to the visual cortex; right world info will go in both eyes, but will take it to the LEFT visual cortex and vice versa

fovea

the center of the retina; where the focus of your vision comes from; peripheral vision is the rest of the retina

trichromatic theory of color vision

you don’t have specialized cones for every color, just the 3 primary colors: blue, green, red

opponent processes

for efficiency, paring together the cells complementary colors into one; “yes means yellow and no means green in one cell;” this is how we have color afterimages

top-down illusion

uses top-down processing; your knowledge/experience tells you how to process info: ex: the arch is actually as wide as it is tall, but doesn’t appear so

Light and color constancy

illusion of color because of lighting; taking context out of the picture can clear up the illusion

oculomotor cues

part of depth perception; involves the muscles related to your eyeballs; they converge and accommodate; the muscles send information rather than the retina

convergence

crossing your eyes, especially to look at something really close, but eyes are parallel when looking at something far away

accommodation

when the lens in your eye change shape depending on if something is close/far away

binocular cues

TWO eyes looking at the world; 2 eyes are needed

retinal disparity

the greater the difference is, the closer the image is to you; like closing one eye then the other but seeing a slight difference in where your finger is relative to you

monocular cues

only one eye needed to be effective

linear perspective

one point perspective

texture gradient

being able to see the textures when something is close to you but it blends together when far away

relative size (size constancy)

the understanding that things in the real world don’t change size; a pencil far away looks small, but you know it didn’t actually get smaller

the phi phenomenon

the perception of motion when there is no motion from still frames

Gestalt Psychology

how our brains simplify the world around us: figure-ground, proximity, similarity, closure, good continuation

figure-ground

tendency to choose one thing as our figure, and everything else becomes the background; the thing in focus has full visual processing; those images where you can look at one thing or another, or choosing to listen to one conversation in a loud room

proximity

things are proximal if they are close in time or space; because these things are close to each other in relative to everything else, they pair together; 8 lines being processed as 4 bars

similarity

if things are similar, they will be processed as one entity/clustered together

closure

filling in what’s not there to make the interpretation easier; some black blobs are just that, but your brain fills it in and sees an image/outline of something

good continuation

presuming gradual change; slow, gradual curves represent one entity; sharp points/things jutting out represent something new

synesthesia

combining of the senses