Sensation and Perception (including TBL quiz questions)

Sensation

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

Weber's Law

the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount)

sensory receptors

sensory nerve endings that respond to stimuli

Perception

the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events

bottom-up processing

analysis that begins with the sensory receptors and works up to the brain's integration of sensory information

top-down processing

information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations

Transduction

conversion of one form of energy into another in our brain

Psychophysics

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

absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time

signal detection theory

a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and alertness.

subliminal

below one's absolute threshold for conscious awareness

difference threshold

the minimum difference between two stimuli required for detection 50 percent of the time (just noticeable difference)

sensory adaptation

diminished sensitivity as a consequence of constant stimulation

perceptual set

a mental predisposition to perceive one thing and not another

audition

the sense or act of hearing

Freequency

number of complete wavelengths that pass through a point during a given time

pitch

a tone's experienced highness or lowness; depends on frequency

middle ear

the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window

what bones are in the middle ear

hammer, anvil, stirrup

cochlea

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

inner ear

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

cochlear implant

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

place theory

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

Gale-Control Theory

the theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain

Hypnosis

a social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur

Dissociation

a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others

posthypnotic suggestion

a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors

Guestation

sense of taste

Olfaction

sense of smell

Kinethesia

our movement sense—our system for sensing the position and movement of individual body arts.

vastibular sense

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

hue

the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth

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

Retnia

a light sensitive membrane in the back of the eye that contains rods and cones which receive an image from the lens and send it to the brain through the optic nerve

contains 5 major classes or neurons photoreceptors

horizontal cells, bipolar cells, amacrine cells and glanglion cells

accomidation

the process by which the eye's lens changes shape to focus near or far objects on the retina

Rods

retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don't respond. sensitive to movement

Cones

retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.

optic nerve

the nerve that carries neural impulses from the eye to the brain

Blindspot

the point at which the optic nerve leaves the eye, creating a "blind" spot because no receptor cells are located there

Fovea

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

three color theory

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

Tetrachromatic color vision

seeing a mosaic of color instead of one shade that's a blend of all of those

Opponant Process Theory

the theory that opposing retinal processes enable color vision

feature detectors

nerve cells in the brains visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement

fusiform face area

a region in the temporal lobe of the brain that helps us recognize the people we know from all angles

paralell processing

the processing of many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions

Gestalt

an organized whole

figure-ground

the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground). seperates foreground from background

grouping

tendency to organize stimuli into coherent groups

depth perception

the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance

visual cliff

a lab device for testing depth perception in infants and young animals

convergence

A binocular cue for perceiving depth; the extent to which the eyes converge inward when looking at an object

retnial disparity

a binocular cue for perceiving depth by comparing images from the retinas in the two eyes, the brain computes distance—the greater the disparity (difference) between the two images, the closer the object.

phi phenomenon

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

perceptual constancy

perceiving objects as unchanging even as illumination and retinal images change

binocular cues

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

monocular cues

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

color receptors are to ________ as opposing retnial processors are to _________

trichromatic theory; opponent process theory

the principle of continuity and closure best illustrate the importance of

top down processing

As Danielle goes outside her eyes receive light energy from the sun. Her eyes then ________ the light energy into neural messages that create what she sees.

transduce

as jennifer waits in her car for her husband to return, the car besides her begins to back out and leave. jennifer then feels that her car is moving. this is due to what

relative motion

Percieving objects as unchanging (having consistent color, brightness, shape, and size) even as illumination and retinal images change

perceptual constancy

_____ are to peripheral movement as ____ are to fine detail

rods; cones