Myers AP Psychlogy Unit 4

absolute threshold

minimal amount of energy required to produce any sensation, 50 percent of the time

binocular cues

In depth cues, such as retinal disparity, that depend on the use of two eyes.

blind spot

place on the retina out where the optic nerve leaves the eye, no receptors (rods/cones) are located here

cones

visual receptor cells; located in retina; works best in bright light; responsible for viewing color; greatest density in the fovea

difference threshold

The minimum difference betwee two stimuli required for detection 50% of the time. We experience the difference threshold as a just noticeable difference.

bottom-up processing

Analysis that begins with thes sensory receptors and works up to the brain’s integration of sensory information.

top-down processing

Constructing perceptions based on our experiences and expectations

selective attention

The focusing of conscious awareness on a particular stimulus, like the cocktail effect (notice your name in a crowd)

inattentional blindness

failing to see visible objects when our attention is directed elsewhere

change blindness

failing to notice changes in the environment.

hue

The dimension of color that is determined by the wavelength of light.

Iris

A ring muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening.

kinesthesis

sense of muscle movement, posture, and strain on muscles/joints; provides information on speed and direction of movement; works with vestibular sense

Lens

The transparent structure behind the pupil that changes shape to help focus images on the retina. Changes shape to refract light to the retina.

psychophysics

The study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.

signal detection theory

States that circumstances, experiences, expectations affect our thresholds

subliminal

Below one’s absolute threshold for conscious awareness

priming

the activation, often unconsciously, of certain associations, thus predisposing one's perception, memory, or response.

sensory adaptation

Diminished sensitivity as a consequence of constant stimulation.

habituation

decreasing responsiveness with repeated stimulation. As infants gain familiarity with repeated exposure to a visual stimulus, their interest wanes and they look away sooner

transduction

Conversion of one form of energy into another. In sensation, the transforming of stimulus energies into neural impulses.

wavelength

The distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from longer/red, shorter/blue

optic nerve

bundle of axons from ganglion cells that carries messages from the eye to the brain

Intensity

The amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave's amplitude.

iris

A ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening.

feature detectors

nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement.

monocular cues

depth cues, such as interposition and linear perspective, available to either eye alone.

perception

the mental process of sorting, identifying, and arranging raw sensory data into meaningful patterns

parallel processing

The processing of several aspects of a problem simultaneously.

opponent process theory

The theory that opposing retinal processes (red-green Christmas, yellow-blue Michigan, white-black) enable color vision.

pitch

auditory experience corresponding to the frequency of sound vibrations, resulting in a higher or lower tone

pupil

The adjustable opening in the center of the eye through which light enters.

retina

the light-sensitive inner lining of the back of the eyeball; contains receptor cells (rods/cones) plus layers of neurons that begin the processing of visual information.

retinal disparity

A binocular cue for perceiving depth: By comparing imaes from the retinas in the two eyes, the greater the disparity (difference) between the 2 images, the closer the object.

rods

visual receptor cell; located in retina; respond to varying degrees of light and dark; responsible for night vision and peripheral vision

accommodation

The process by which the eyes lens changes shape to focus near or far object on the retina.

sensation

The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.

fovea

The central focal point in the retina, around which the eye's cones cluster.

audtition

The sense of hearing.

frequency

The number of complete wavelengths that pass a point in a given time (for example, per second).

middle ear

The chamber between the eardrum and cochlea containing three tiny bones (Hammer, Anvil, and Stirrup) that concentrate the vibrations (conduction) of the eardrum on the cochlea's oval window.

conduction hearing loss

Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.

sensorineural hearing loss

Hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness.

cochlear implant

a device for converting sounds into electrical signals and stimulating the auditory nerve by electrodes threaded into the cochlea

cochlea

A coiled, bony, fluid-filled tude in the inner ear through which sound waves trigger nerve impulses.

Young-Helmholtz trichromatic theory

The theory that the retina contains 3 different color receptors -one most sensitive to red, one green, one blue- which, when stimulated in any combination, can produce perception of any color.

inner ear

The innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.

Place theory

In hearing, the theory that links the pitch we hear with 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.

vestibular sense

The sense of body movement and position, including the sense of balance.

Weber's law

Ernst Weber; the principle that accounts for how one notices the difference threshold for any change must be proportional

Gate-control theory

The spinal cord contains a "gate" that blocks pain signals or allows them to pass on to the brain. It's opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in large fibers or information coming from the brain.

Sensory interaction

The principle that one sense may influence another, as when the smell of food influences its taste.

perceptual consistancy

perceiving objects as unchanging (having consistent shapes, size, lightness, and color) even as illumination and retinal images change.

David Hubel - Torsten Wiesel

discovered feature detector groups of neurons in the visual cortex that respond to different types of visual images

Gustav Fechner - Ernest Weber

Weber’s Law + Psychophysics.

Depth perception

Ability to see objects in three dimension although the image that strike the retina are two-dimensional; allows us to judge distance

Visual cliff

Laboratory device for testing depth perception in infants and young animals

Phi phenomenon

Illusion of movement created when two or more adjacent lights blink on and off in quick succession

Color constancy

Perceiving familiar objects as having consistent color, even if changing illumination alters the wave-lengths reflected by the object

Perceptual adaptation

In vision, the ability to adjust to an artificially displaced or even inverted visual field

Perceptual set

A mental predisposition to perceive one thing and not another

Parapsychology

Study of paranormal phenomena, including ESP and psychokinesis

Extrasensory perception (ESP)

Controversial claim that perception can occur apart from sensory input; telepathy, clairvoyance, and precognition

Accommodation

Process by which the eye lens changes shape to focus near or far objects on the retina

Gestalt

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

Grouping

The perceptual tendency to organize stimuli into coherent groups.

Figure-ground

The organization of the visual field into objects (the figures) hat stand out from their surroundings (the ground)

Visual Cliff

A laboratory device for testing depth perception in infants and young animals.