AP Psych sensation and perception

Sensation/Perception

how we construct our perceptions of the external world

Sensation

The detection of physical energy from the environment to neural signals

Absolute threshold

The minimum stimulation necessary to detect a particular light, sound, pressure, taste, or odor 50% of the time

Signal Detection Theory

Theory that there is not a universal absolute threshold and it depends on the situation or experience of a person

Just Noticeable difference

The moment you detect a change in existing stimuli

Webers Law

For a difference to be noticeable, it must differ at a constant proportion (5 lb to 10 lb vs. 500 to 505 lb weight)

Sensory adaptation

Diminishes sensitivity as a result of constant stimulation

Habituation

a psychological learning process where you decrease you response/attention to a stimulus after being repeatedly exposed to it

Subliminal Stimulation

When stimuli are below one absolute threshold for conscious awareness

Vision

our eyes convert light energy into neutral messages, where our brain processes into what we see

The retina

Has receptor cells called rods and cones

Rods

1. Send Combined messages

2. Works with peripheral vision

Cones

Perceive color

Blind spot

occurs where optic nerve leaves the eye

Parallel Processing

We are able to process aspects of a problem simultaneously instead of a step-by-step process (EX: Recognizing a face)

YHT Theory

Our threshold for color is so low that we can discriminate 7 million different color variants

(The retina contains 3 different color receptors, Red, Green, Blue)

Opponent Process Theory

Opposing retinal processes enable color vision

(Each of the 3 retinal color receptors have opposites)

3 Dimensions of color

Hue, Brightness, Saturation

Hue

Whether light reflected off object looks red, green, blue, or other

Brightness

How light/dark a color appears

Saturation

The depth/richness of the color

Nearsightedness

Closer objects are clearer

Farsightedness

Farther objects are clearer

Color vision deficiency (Colorblindness)

See colors differently/harder to differentiate colors

Prosopagonia

Can’t recognize faces

Blindsight

Able to discriminate visual stimuli without noticing

Soundwaves

Vibrating molecules of air

Frequency

The number of complete wavelengths that pass a point in a given time

Outer ear

Channels sound waves through auditory canal to eardrum

Middle Ear

Transmits vibrations to cochlea in the inner ear

Organ of cort

A structure in the cochlea of the inner ear which produces nerve impulses in response to sound vibrations

Conduction Hearing loss

When hearing loss is due to problems with the ear canal, ear drum, or middle ear and little bones

Sensorineural Hearing Loss

When hearing Loss is due to problems of the inner ear or auditory nerves

Place Theory

Location of the hairs in cochlea determines frequency

Frequency Theory

pulses travel up auditory nerve at a rate matching whatever tone you are hearing exactly

Volley principle

Neural cells alternate firing

Sound Localization

The ability to tell the direction a sound originates from

Why pain is important

Because it makes us aware something is wrong

Top Down Processing

using previous knowledge/experiences to construct perceptions

Bottom Up processing

No prior knowledge of something, progression from individual elements to whole

Selective attention

Our senses can take 11 million bits of info per sec, but we only process 40

Cocktail Party effect

The ability to attend to one voice among many

Change blindness

failure to see changes in the environment

Inattentional blindness

Inability to see an object or a person amidst an engrossing scene (moonwalking bear)

Visual Capture

The tendency for vision to dominate the other senses

Gestalt

We integrate pieces of info into wholes

Proximity grouping

grouping figures based on closeness

Similarity grouping

grouping similar figures together

Continuity grouping

Objects are seen as connected rather than separate

Closure

We fill in gaps to create a complete object

Visual Cliff

Lab device that tests depth perception in infants and animals

Binocular cues

Depth perception of objects that depend on 2 eyes

Retinal Disparity

The difference between 2 images created with binocular cues

Convergence

our eyes move together to focus on an object that is close and move farther apart for a distant object

Monocular cues

available to either eye or alone

Horizontal-Vertical Illusion

Vertical dimensions appear longer than horizontal dimensions

Relative size

Things are further appear smaller

Interposition

If an object is blocking your view of another, it appears closer

Relative Clarity

Clear objects are closer than hazy ones

Texture Gradient

Distinct texture is perceived as closer than indistinct texture

Relative Height

Higher objects are perceived as further away

Linear Perspective

Parallel lines appear to converge with distance

Light/ Shadow

Lighter images appear closer than dimmer objects

Relative motion

when in motion, objects that are stable seem to be moving backwards. Things further away seem to be moving slower

Phi Phenomenon

Lights turning off and on in a line appear like the light is moving (Christmas lights video)