Ch. 6 Sensation And Perception

Front 1

Sensation

Back 1

the process by which our sensory receptors and nervous system receive and represent physical energy from the environment

Front 2

Perception

Back 2

the process by which we organize and interpret sensory information

Front 3

Bottom-up processing

Back 3

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

Front 4

Top-down processing

Back 4

information processing guided by higher-level processes

Front 5

Psychophysics

Back 5

the study of relationships between the physical characteristics of stimuli and our psychological experience of them

Front 6

Absolute Threshold

Back 6

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

Front 7

Signal detection theory

Back 7

explains precisely how when we detect the presence of a faint stimulus. Detection depends partly on experience, expectations, motivation, and alertness.

Front 8

Subliminal

Back 8

a stimulus that is below the absolute threshold for conscious awareness

Front 9

Priming

Back 9

the activation, often unconsciously, of an association by an imperceptible stimulus, the effect of which is to predispose a perception, memory, or response

Front 10

Difference threshold

Back 10

the minimum difference between two stimuli required for detection 50 percent of the time

Front 11

Weber's law

Back 11

states that the just noticeable difference between two stimuli is a constant minimum proportion of the stimulus

Front 12

Sensory adaptation

Back 12

refers to the decreased sensitivity that occurs with continued exposure to an unchanging stimulus

Front 13

Transduction

Back 13

refers to the process by which receptor cells in the eyes, ears, skin, and nose convert stimulus energies into neural impulses

Front 14

Wavelength

Back 14

refers to the distance from the peak of one light wave to the next, gives rise to the perceptual experiences of hue, or color, in vision

Front 15

Intensity of light and sound

Back 15

determined by the amplitude of the waves and is experienced as brightness and loudness, respectively

Front 16

Pupil

Back 16

the adjustable opening in the eye through which light enters

Front 17

Iris

Back 17

a ring of muscle tissue that forms the colored part of the eye that controls the diameter of the pupil

Front 18

Lens

Back 18

the transparent structure of the eye behind the pupil that changes shape to focus images on the retina

Front 19

Retina

Back 19

the light-sensitive, multilayered inner surface of the eye that contains the rods and cones as well as neurons that form the beginning of the optic nerve

Front 20

Accomodation

Back 20

the process by which the lens of the eye changes shape to focus near objects on the retina

Front 21

Rods and cones

Back 21

visual receptors that convert light energy into neural impulses. The rods are concentrated in the periphery of the retina, the cones in the foves. The rods have poor sensitivity; detect black, white, and gray; function well in dim light; and are needed for peripheral vision. The cones have excellent sensitivity, enable color vision, and function best in daylight or bright light.

Front 22

Optic nerve

Back 22

comprised of the axons of the retinal ganglion cells, carries neural impulses from the eye to the brain

Front 23

Blind spot

Back 23

the region of the retina where the optic nerve leaves the eye. Because there are no rods or cones in this area, there is no vision here

Front 24

Fovea

Back 24

the retina's point of central focus. it contains only cones; therefore, images focused on the fovea are the clearest

Front 25

Feature detectors

Back 25

located in the visual cortex of the brain, are nerve cells that selectively respond to specific visual features, such as movement, shape, or angle. Feature detectors are evidently the basis of visual information processing.

Front 26

Parallel processing

Back 26

information processing in which several aspects of a stimulus, such as light or sound, are processed simultaneously.

Front 27

Young-Helmholtz trichromatic theory

Back 27

maintains that the retina contains red-, green-, and blue-sensitive color receptors that in combination can produce the perception of any color. This theory explains the first stage of color processing.

Front 28

Opponent-process theory

Back 28

states that color vision depends on pairs of opposing retinal processes (red-green, yellow-blue, and white-black). This theory explains the second stage of color processing.

Front 29

Audition

Back 29

refers to the sense of hearing

Front 30

Frequency

Back 30

directly related to wavelength: longer waves produce lower pitch; shorter waves produce higher pitch.

Front 31

Pitch

Back 31

determined by its frequency, that is, the number of complete wavelengths that can pass a point in a given time

Front 32

Middle ear

Back 32

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

Front 33

Cochlea

Back 33

the coiled, bony, fluid-filled tube of the inner ear through which sound waves trigger neural impulses

Front 34

Inner ear

Back 34

contains the semicircular canals and the cochlea, which includes the receptors that transform sound energy into neural impulses. Because it also contains the vestibular sac, the inner ear plays an important role in balance, as well as in audition

Front 35

Place theory

Back 35

states that we hear different pitches because sound waves of various frequencies trigger activity at different places on the cochlea's basilar membrane

Front 36

Frequency theory

Back 36

presumes that the rate, or frequency, of nerve impulses in the auditory nerve matches the frequency of a tune, thus enabling us to sense its pitch

Front 37

Conduction hearing loss

Back 37

refers to the hearing loss that results from damage in the mechanics of the outer or middle ear, which impairs the conduction of sound waves to the cochlea

Front 38

Sensorineural hearing loss

Back 38

hearing loss caused by damage to the auditory receptors of the cochlea or to the auditory nerve due to disease, aging, or prolonged exposure to ear-splitting noise

Front 39

Cochlear implant

Back 39

an electronic device that converts sounds into electrical signals that stimulate the auditory merve

Front 40

Kinesthesis

Back 40

the sense of the position and movement of the parts of the body

Front 41

Vestibular sense

Back 41

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

Front 42

Melzack and Wall's gate-control theory

Back 42

states that a "gate" in the spinal cord determines whether pain signals are permitted to reach the brain. Neural activity in small nerve fibers opens the gates; activity in large fibers or information from the brain closes the gate

Front 43

Sensory interaction

Back 43

the principle that one sense may influence another

Front 44

Gestalt

Back 44

"organized whole" The Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes

Front 45

Figure-ground

Back 45

the organization of the visual field into two parts: the figure, which stands out from its surroundings, and the surroundings, or background

Front 46

Grouping

Back 46

the perceptual tendency to organize stimuli into coherent groups. Gestalt psychologists identified various principles of grouping

Front 47

Depth perception

Back 47

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

Front 48

Visual cliff

Back 48

a laboratory device for testing depth perception, especially in infants and young animals. In their experiments with the visual cliff, Gibson and Walk found strong evidence that depth perception is at least in part innate

Front 49

Binocular cues

Back 49

depth cues that depend on information from both eyes

Front 50

Retinal disparity

Back 50

refers to the differences between the images received by the left eye and the right eye as a result of viewing the world from slightly different angles. It is a binocular depth cue, since the greater the difference between the two images, the nearer the object.

Front 51

Monocular cues

Back 51

depth cues that depend on information from either eye alone

Front 52

Phi phenomenon

Back 52

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

Front 53

Perceptual constancy

Back 53

the perception that objects have consistent lightness, color, shape, and size, even as illumination and retinal images change

Front 54

Color constancy

Back 54

the perception that familiar objects have consistent color despite changes in illumination that shift the wavelengths they reflect

Front 55

Perceptual adaptation

Back 55

our ability to adjust to an artificially displaces or even inverted visual field. Given distorting lenses, we perceive things accordingly but soon adjust by learning the relationship between out distorted perceptions and the reality

Front 56

Perceptual set

Back 56

a mental predisposition to perceive one thing and not another

Front 57

Human factors psychology

Back 57

explores how people and machines interact and how machines and physical environments can be made safe and easy to use

Front 58

Extrasensory perception (ESP)

Back 58

refers to the controversial claim that perception can occur without sensory input. Supposed ESP powers include telepathy, clairvoyancy, and precognition

Front 59

Parapsychology

Back 59

the study of ESP, psychokineses, and other paranormal forms of interaction between the individual and the envrionment