AP PSYCH UNIT 2 PART 1

sensation

stimulation of the sense organs, the raw data, nerve impulses

perception

selection, organization and interpretation of sensory info, how we make sense of the info, what influences our perception?

bottom up processing

going from sensation to perception, building your overall perception from: info you get from the senses, putting it all tg to form a perception

top down processing

uses past experiences to take info from the senses and construct your perception

psychophysics

study of how physical stimuli are translated into psychological experience, how we take in the world and make sense of it.

transduction

convert one form of energy into another that your brain can use. Converting waves(audio, light) into neural impulses

stimuli

anything in the environment can be detected by senses. Detection depends on the organism doing the detecting.

selective attention

we attend to a small amount of incoming stimuli at any given moment

cocktail party effect

ability to pay attention to only 1 voice amongst many other voices at a party, but you are able to detect your name in the background

inattentional blindness

failing to see visible objects when our attention is directed elsewhere

Absolute threshold

it is not absolute, the minimum stimulus intensity that can be detected 50% of the time, vision, hearing, taste, smell, touch

difference thresholds or just noticeable differences

the smallest difference in stimulus intensity that a specific sense can detect

Weber’s law PART 1

the change needed is proportional to the original intensity of the stimulus

Weber’s Law PART 2

the more intense the stimulus the more change is needed to notice the diff

signal detection theory

it predicts how and when we detect the presence of a stimulus , it assumes that “absolute threshold” is dependent on context/situation

subliminal message

registration of sensory input without conscious awareness, perception below threshold

Sensory Adaptation/Habituation

the diminished sensitivity as a consequence of constant stimulation, automatic process, keeps us tuned into changes

visual light

the 3 properties of light and how they allow us to visualize the world

light

travels in waves

amplitude

height of the waves, effects the perception of the brightness

wavelength

distance between peaks(pitch), effects the perception of color

purity

how mixed the wavelengths are, purer the color is the more saturated (rich less white) it is

lens

transparent structure that focuses the light rays falling on the retina, it is able to perform accommodation or adjustments that alter visual focuses

the lens of the eye gets fatter/rounder up close

the lens of the eye gets flatter in order to see things far off

near sighted

objects that are close up are seen clearly but far off is blurry

far sighted

objects far off are seen clearly but near ones are blurry

the pupil

the opening in the center of the iris that permits light to pass into the rear chamber of the eye , when it is constricted it lets light in resulting in a sharper image, when it is dilated it lets more light in but the images is less sharp

the retina

the inside back surface of an eye that , absorbs light, process image, sends visual image to the brain

optic disc

hole in the retina where the optic nerve fibers exit the eye, blind spot

rods

vastly out number cones, more sensitive to light than cones, they are specialized to see better at night— no bright light, more on the sides of the retina which helps with peripheral vision

cones

used for daytime and color vision, mostly concentrated in the center of the retina, don’t respond well to low light, comes allow for better visual activity(sharpness)

fovea——(cones)

area in the center of the eye-only cones

dark adaptation

the process that makes your eye more sensitive to low light, allows to see more in the dark

light adaptation

the process that makes your eye less sensitive to light , increase visual activity, see better in better light

neural pathway

once image hits the retina—

1) rods and cones funnel the image to receptive fields

2) receptive fields is a retina area that, when stimulated affects firing of bipolar cells

3) from there it is sent to ganglion cells, then that image is send down to the optic nerve

4) optoc nerve is a group of axons that go back to the brain

vision and the brain

images from the inside of each eye pass to the opp. side occipital lobe, images from outside of the eye go to the same side occipital lobe.

the point at which the optic nerve goes 2 pathways:

main: perception of color, from contrast, and motion

2ND: perception of motion and coordination of visual input which other sensory input

the visual cortex

the part of the brain that interprets the visual image

feature detectors

neurons that respond to very specific features

ventral stream

processes what visual stimuli are(what pathway), forms(shapes), color, damage to this stream can result in agnosia and proagnosia

dorsal stream

where visual stimuli are (where pathway), motion, depth

distinguishing color

color is an interpretation not a physical property of light

trichromatic theory of color vision

human eye has 3 types of color receptors (cones), each receptor is sensitive to different wavelengths, seeing different colors is simply a minute of these 3 different color receptors: red, green, blue

color blindness

deficiencies is in the ability to distinguish among colors, these defecienccies help to prove this theory

complementary colors

pairs of colors that produce gray tones when mixed together,

afterimage

a visual image that persits after a stimulus is removed

the theory

the sensory receptors come in pairs, red/green, yellow/white, black/white, 1 color is stimulated, other inhibited, perception of color depends on receptors that make opposite receptors

cones follow the trichromatic theory

the eye has 3 types of cones that are sensitive of specific wavelengths(colors)

opponent process theory

neurons respond in opp. ways to: red vs green, blue vs yellow

amplitude

loudness, decibels: 85 DB is dangerous

wavelength

pitch, frequency, cycle per second(hertz)

purity

timbre(quality), fewer waves=purer sound

pinna (EXTERNAL EAR)

sound collecting cone, sound is funneled into the ear canal

ear canal(EXTERNAL EAR)

sends sound to the eardrum

ear drum(external ear)

membrane that vibrates in response to sound waves

ossicles(middle ear)

Cochlea(INNEAR EAR)

fluid filled, coiled tunnel that contains the receptor for hearing

place theory

perception of pitch depends on vibrations at different portions(places)along the basilar membrane, diff hair cells respond to diff pitches

frequency theory

perception of pitch is due to the rate at which the entire basilar membrane vibrates , high pitch=fast vibrations, lower pitch=slower vibrations

reconciling theories

both have flaws, valid in part, waves peak at particular places in the cochlea.

sound localization

2 ears working together, stereophonic hearing, 2 ears are better than 1

conduct deficiencies

damage to the mechanical systems in the ear, eardrum and ossicles, WHY: music too loud, disease, old age.

sensorineural deafness

damage to the hair cells on the cochlea, damage to the auditory nerve, these are the more common forms of deafness.

mechanical(physical stimuli for touch)

tactile stimulation(pressure), pain

thermal(physical stimuli for touch)

hot, cold

chemical energies (physcial stimuli for touch)

receptive fields(feeling pressure)

nerve receptors located on the skin across the body. When stimuli sends signals through the thalamus to the opposite side of the sensory cortex.

fast pathway (1st pathway for pain)

registers sharp localized pain, relays pain to the cortex in a fraction of a second, allows us to react quickly

slow pathway (2nd pathway to pain)

the pain that you get after initial injury, lags behind a few seconds

perception of pain

the perception of pain is hihgly subjective but absolutely necessary for survival

gate control theory (blocking pain perception)

incoming pain signals must pass through a gate, gate can be closed blocking pain signals not an anatomical structure but rather a pattern of neural activity

what can close THE GATE?

signals from the brain: attention, expectation, signals from other peripheral receptors.

endorphins

the bodies natural pain killers

Taste buds- The Gustatory System

taste cells that line the trenches of tiny bumps on the tongue, absorbs chemicals dissolved in saliva, these chemicals trigger neural impulses that are routed through the thalamus to the cortex.

4 basic tastes

bitter, sour, sweet, salty, umami

taste

like smell, taste is chemical sense, tells you basic qualities of what’s going in your mouth

flavor

made up of taste,smell, texture, spice, sight, expectation, temperature, setting, memory

influences of perception

age, culture, genetics, learning

olfactory cilia (smell receptors)

air like structures in the nasal passage, send a neural impulse into the olfactory bulb

kinesthetic sense

tell us where our body parts are, receptors located in our muscles and joints.

vestibular sense

tells us where our body is oriented in space, our sense of balance, located in our semicircular canals in our ears.

perception=interpretation

not a passive process, interpretation needs sensory input

perceptual constancies

objects change in our eyes constantly as we or they move, but we are able to maintain stable perception

schema

preconcieved idea based on past experiences

perceptual set

a readiness to perceive sensory info in a certain way, these can be manipulated in order to influence perception

selection

what a person is focused on,

feature analysis

the process of detecting specific elements in visual input and assembling them into a more complex form, assumes bottom-up processing

phi phenomenon (gestalt psychology)

illusion of movement due to presenting in rapid sucession

gestalt principles

dividing visual info into figure and ground

figure(gestalt principles)

the thing being looked at

ground(gestalt principles)

the background

proximity (gestalt principles)

the things that are near eachother are seen as being together

closure (gestalt principles)

we group elements to create a sense of closure

similarity(GPs)

we group stimuli that are similar

simplicity(GPs)

we group things that makes good figure

continuity(GPs)

we group things in a way that creates smooth continuous.

perceptual hypothesis

expectation influence, the context in which you are viewing something influences the way we perceive it

depth perception

visual cliff experiment, we see depth by using 2 cues.

binocular cues

2 eyes see things just a little different. The difference gives us cues on distance

retinal disparity(binocular cues)

images within 25 ft project differently on each retina, right and left eye sees a slightly different image, the closer the object the greater the disparity.

convergence(bioncular cues)

sensing the eyes converging toward each other as they focus on closer objects, size of an image on our retina, whether or not the lens is flat or fatter.