psych exam 2

Sensation

detecting physical energy with our sense organs (eyes, ears, skin, nose, tongue)

Perception

the brain’s interpretation of the raw sensory information

Do our Perceptions always match our Sensations?
Or, do our Perceptions always match physical reality?
NO!!
8

Do out perceptions always match our sensations?

no

Do our perceptions always match physical reality?

no 

illusion

the way we perceive a stimulus doesn’t match its physical reality. tell us that perception involves some processing of information

You are lying in bed and you think that you might detect something touching your face. Then you realize it is a spider and jump out of bed! Deciding whether or not something is there involves ____. Recognizing it as a spider involves ____. 

sensation, perception

transduction

conversion of an external stimulus into a neural signal

sensory receptors

specialized cells designed to convert a certain kind of external information into a neural signal

sensory adaptation 

sensory neurons adjust their sensitivity based on recent stimulus history 

aftereffects

are opposing sensory or perceptual distortions that occur after adaptation 

A loud, low sound such as that of a heavy train passing by would be caused by sound waves that are ____.

high amplitude, low frequency

Some insects can see ultraviolet light in ranges that are invisible to humans. Ultraviolet light is more toward to blue ned of the spectrum than visible blue light. Ultraviolet light is too ___ for humans to see. 

high frequency 

sound

vibration, mechanical energy that travels through some medium (without a medium there is no sound)

what is sound derived from?

tiny vibrations

what creates waves (sound)?

compressed and expanded air molecules 

audition

the range of human hearing (20,000-20 Hz)

pitch

frequency of sound wave measured in Hz

short wavelength = ___ frequency = ____ pitch

high, high

loudness

heigh (amplitude) of a sound wave, measured in dB

timbre

quality of complexity of a sound

what sound property causes different musical instruments to sound different when playing the same note?

timbre

outer ear

funnels sound to ear drum, includes pinna and ear canal

middle ear

transmits sounds from ear drum to inner ear, includes ossicles

ossicles

hammer, anvil, stirrup

inner ear

transducer sound, includes cochlea

cochlea

transduction accomplished by movement of hair cells (cilia) 

function of ear

outer ear funnels sound toward ear drum, ear drum vibrates - moving ossicles in middle ear, ossicles cause displacements of basilar membrane in cochlea (inner ear), basilar membrane moves - hair cells bend, excited hair cells cause action potentials, information is sent to brain via auditory nerve

place theory

specific locations on the basilar membrane match tones with specific pitches, base vibrates to high frequency sounds, end vibrates to low frequency sounds

frequency theory

neuron firing rate matches pitch, sound frequency corresponds to action potential frequency

volley principle

clusters of nerve cells can fire together (modification of frequency theory)

binaural cues

depending on having 2 ears

intramural level difference

sound coming from right side is more intense in right ear - bc it does not have to pass through head

interaural timing difference

sound from the right side reaches the right ear first

conductive deafness

malfunctioning of the ear drum or ossicles

sensorineural hearing loss

neural signals are not transmitted from cochlea

noise induced hearing loss

damage to hair cells due to loud noises

Where are the hair cells (sensory receptors for hearing) located?

in the cochlea

which frequencies are encoded by neurons firing in synchrony with the sound waves?

very low frequency sounds

sclera

white part of eye

pupil

circular hole where light enters

iris

colored portion of the eye that controls pupil size (amountt of light being let in)

cornea

curved, transparent layer covering the iris and pupil that helps focus light 

lens

oval shaped disc that bends light

accommodation

changing of the lens’ shape to focus on near/ far objects

myopia

nearsightedness, eye is too long

hyperopia

farsightedness, eye is too short

retina

membrane at back of the eye responsible for converting light into a neural signal 

fovea

central portion of the retina, responsible for visual acuity, high density of cones, very small

acuity 

sharpness of vision 

rods

respond under low levels of light, not color sensitive, more common outside of fovea

cones

sensitive to fine detail, primarily located in fovea, color sensitive, less plentiful than rods

saccades

small jerky movements of the eye allowing for rapid changes of focus, goal is the put the fovea on a new location 

optic nerve 

bundle of axons that travels from the retina to the brain 

blind spot

area of retina where the optic nerve exits the eye

the highest density of cones in the retina is found ____

in the fovea

what part of your visual system helps you to see things in low levels of light?

rods

hue

the color of light corresponds to wavelength

trichromatic theory

color vision is based on three primary colors : blue, green, and red (3 types of cones)

opponent process theory 

we perceive colors in terms of three pairs of opponent colors (R-G, B-Y, B-W)

color blindness

inability to see some or all colors, due to loss of one or more types of cones

depth perception

ability to judge distance and spatial relations

binocular depth cues

Involve two eyes

monocular depth cues

involve one eye

binocular disparity

each eye slightly different images, brain can judge depth 

convergence

eyes converge to see near objects

relative size

distant objects look smaller than closer objects

texture gradient

texture is more clear on closer objects

interposition

closer objects appear in front of distant objects

linear perspective

parallel lines converge with distance

height plane

distant objects appear higher than closer objects

light and shadow

shadows can tell us about form

motion parallax

closer objects pass more quickly than distant objects

perceptual constancy

perceive stimuli as constant across varied conditions

shape constancy

perceived shape is constant, even though shape of the image (on retina) varies 

size constancy

perceive stimuli as consistent across varied conditions

color constancy

perceive stimuli as consistent across varied conditions

psychophysics

the study of how our sensations (psychological events) correspond to the physical events in the world

absolute threshold 

the lowest level of a stimulus needed for the nervous system to detect a change 50% of the time 

just noticeable difference

the smallest change in the intensity of a stimulus that we can detect

weber’s law

the stronger the stimulus, the bigger the change needed to detect it , the amount of stimulus energy required to produce a JND constant fraction of stimulus intensity 

Sue is taking a hearing test and trying to detect very quiet sounds. One very quiet sound is so hard to detect that she misses hearing it about 70% of the time. The sound is ___ her absolute threshold. 

below 

signal detection theory

how stimuli are detected under different conditions

signal

what you are trying to detect

noise

similar stimuli that might compete with the signal and interference with your ability to detect the signal

signal to noise ratio

difficult of detecting the signal depends in the strength of the signal in relation to the strength of the noise

You were searching for your lost phone, which has an orange case. When you see a part of a orange t shirt peeking from a pile of clothes, for a moment you think it is your phone! You have just experienced a ___. 

a false alarm 

You were searching for your lost phone, which has an orange case. When you see a part of an orange, it is your phone. You have just experienced a ___. 

hit 

What will happen if you adjust your response criterion so that you never have any misses?

It will increase false alarms

What will happen if you increase your rate of correct rejections?

your rate of misses will increase 

dichotic listening

play different information through ear ear of headphones. information reported init from the attended ear

cocktail party effect

happens when important information pops out in a conversation that you are not attending 

inattentional blindness

occurs when unattended stimuli are ignored as if they weren’t there

chane blindess

a version of this that occurs when you fail to detect obvious changes in your environment 

bottom - up processing

constructing a representation from parts and basic features

top-down processing

influenced by previous experience and knowledge

perception - top down or bottom up

includes top-down processing , which can change what we report about sensations 

sensation - top down or bottom up

bottom up

perceptual sets

set formed when our expectations influence our perceptions

figure ground separation

your visual system automatically tries to identify figures, figures are integrated units of perception 

Gestalt principles 

rules that govern how we perceive objects as wholes within their overall context