AP Pyschology Unit 4

Sensation

Bringing in information through our senses.

Energy Senses

Vision, Hearing (audition), Touch (cutaneous)

chemical senses

gustation (taste) and olfaction (smell)

bodily senses

Vestibular (inner ear) and kinesthetic(receptors in muscles and joints)

Transduction

Process of turning environmental information into neural impulses.

Perception

How our brain makes sense of the information we get from our senses.

absolute threshold

The smallest amount of a stimulus necessary for the stimulus to be detected 50% of the time.

Stimulus

A thing or event that evokes a functional reaction/response

difference threshold

The smallest amount by which a stimulus can be changed to be different and the difference can be detected 50% of the time.

Weber's Law

The size of the JND is proportional to the intensity of the stimulus (the JND is large when the stimulus intensity is high and the JND is small when the stimulus intensity is low).

sensory adaptation

Reduction of sensitivity to a stimulus due to it being constant

signal detection theory

Seeks to explain the effects of distractions we experience in the world

false positive

Detecting a stimulus when it's not present.

false negative

Not detecting a stimulus when it is present.

selective attention

Paying attention to something and filtering out the unimportant stimuli

cocktail party phenomenon

When you're at a party, everyone is talking but you only pay attention to the conversation you're in and you filter out the other sounds. However, if someone calls your name across the room, your attention is drawn in that direction.

top-down processing

Uses previous knowledge and is conceptually driven.

bottom-up processing

Stimulus driven processing

Linear Perspective

Lines meet at the vanishing point used to see depth.

Interposition cue

Objects that block the view of other objects must be closer to us.

texture gradient

The closer you are, the more texture you can see. The texture is less visible when farther away.

trichromatic theory

Three types of cones in the retina- red, blue and green. They are activated in different combinations to produce all the colors of visible spectrum.

opponent process theory of color vision

The sensory receptors arranged in the retina cone in bipolar pairs: red/green pairs, yellow/blue pairs, and black/white pairs. This explains color blindness and afterimages better.

dichromatic color blindness

Can only perceive two primary colors and combinations of those two colors.

retinal disparity

The brain compares retinal images from the two eyes. Each of our eyes sees any object from a slightly different angle.

convergence

Closer objects must make eyes move toward each other to keep focus

parallel processing

The ability of the brain to simultaneously process incoming stimuli of differing quality.

subliminal

When stimuli are below our absolute threshold.

inattential blindness

failing to see visible objects when our attention is directed elsewhere

change blindness

failing to notice changes in the environment

top-down attention

decision making attention

bottom-up attention

attention that grabs focus

sensory cortices

Responds to unexpected stimuli to grab your focus

proximity

objects that are close together are more likely to be perceived as belonging in the same group.

similarity

Objects that are similar in appearance are more likely to be perceived as belonging in the same group.

Continuity

Objects that form a continuous form (such as a trail or a geometric figure) are more likely to be perceived as belonging in the same group.

Closure

Similar to top-down processing. objects that make up a recognizable image are more likely to be perceived as belonging in the same group even if the image contains gaps that the mind needs to fill in.

mirror neurons

The brain imitates the actions of others through analyzing.

Ponzo Illusion

An illusion of size in which two objects of equal size that are positioned between two converging lines appear to be different in size. Also called the railroad track illusion.

Muller-Lyer Illusion

illusion of line length that is distorted by inward-turning or outward-turning corners on the ends of the lines, causing lines of equal length to appear to be different

direct perception

the interpretation of sensory information directly by the brain as opposed to perceptual interpretation resulting from cognitive processing

monocular cues

depth cues available to either eye alone

binocular cues

depth cues that depend on having two eyes

constancy

Ability to maintain constant perception of an object despite other changes.

size constancy

Closer objects produce bigger images, but we take distance for size estimating.

shape constancy

Objects from different angles = different shapes, we know that the shape of an object is constant.

brightness constancy

Objects have constant colors even if the reflecting light changes.

phi phenomenon

Series of light bulbs- turned on and off at a particular rate will appear to be one moving light.

stroboscopic effect

Images in a series of still pictures presented at a certain speed will appear to be moving

autokinetic effect

If light is projected steadily on a wall of a dark room, people will report seeing it move.

Ossicles

three tiny bones in the middle ear (hammer/malleus, anvil/incus, stirrup/stapes)

tympanic membrane

The eardrum. A structure that separates the outer ear from the middle ear and vibrates in response to sound waves.

sound waves

Created by vibrations that travel through air and collected by your ears.

Frequency

Known as wave length that determines pitch in megahertz.

Amplitude

Height of a wave that determines loudness of sound in decibels.

oval window

membrane at the enterance to the cochlea through which the ossicles transmit vibrations

cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

Organ of Corti

Center part of the cochlea, containing hair cells, canals, and membranes

place theory

in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated

frequency theory

in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

conduction deafness

An inability to hear resulting from damage to structures of the middle or inner ear.

nerve deafness

Hearing loss created by damage to the hair cells or the auditory nerve fibers in the inner ear.

indentation

Temperature changes that our brain interprets

pain receptors

stimulated by tissue damage

gate-control theory

Explains how we perceive pain and states that some pain messages have a higher priority than others.

Papillae of the tongue

taste buds

olfactory bulb

Linked to 100 different types of smell receptors and gathers messages from the olfactory receptor cells and sends this info to the brain.

olfactory receptor cells

the sensors responsible for smell

auditory nerve

the nerve that carries impulses from the inner ear to the brain, resulting in the perception of sound

semicircular canals

three tiny, fluid-filled tubes in your inner ear that helps maintain balance. The liquid inside sloshes around and moves the tiny hairs when your head moves.

basilar membrane

It forms the base of the Organ of Corti.

middle ear

Contains the three ossicles

Afterimage

A visual image that persists after a stimulus is removed.

Gestalt

an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes.

perceptual constancy

perceiving objects as unchanging even as illumination and retinal images change

figure-ground

the tendency to perceive objects, or figures, as existing on a background

dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks

sequential processing

the processing of one aspect of a problem at a time; used when we focus attention on new or complex tasks

blind spot

the point at which the optic nerve leaves the eye

Law of Pragnanz

the simplest organization, requiring the least cognitive effort, will emerge as the figure

Fovea

Contains the highest concentration of cones

perceptual set

a mental predisposition to perceive one thing and not another

accommodation

the process in which the lens focuses images on the retina by bending its shape

Cones

Responsible for seeing fine detail and color

Retina

Light sensitive layer of the eye; contains rods and cones

visual cliff experiment

created by E.J. Gibson, used to determine when infants can perceive depth

Rods

Retinal receptors that detect black, white, and gray. Sensitive to dim light but not colors.

cutaneous senses

The skin senses that register sensations of pressure, warmth, and cold.