Psychology Chapter 6

Relative motion

As we move, objects that are actually stable may appear to move.

pupils

Cats are also able to open their___ much wider than we can, which allows more light into their eyes so they can see better at night.

figure; ground

In terms of perception, a band's lead singer would be considered (figure/ground), and the other musicians would be considered (figure/ground).

Linear perspective

Parallel lines appear to meet in the distance. The sharper the angle of convergence, the greater the perceived distance.

McGurk

Seeing the mouth movements for ga while hearing ba we may perceive da—a phenomenon known as the___ effect.

receptor cells

The retina doesn't "see" a whole image. Rather, its millions of ____convert particles of light energy into neural impulses and forward those to the brain. There, the impulses are reassembled into a perceived, upright- seeming image.

cochlea [KOHK-lee - uh]

a coiled, bony, fluid - filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses.

visual cliff

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

bottom-up; top-down

feeling pain reflects both___ sensations and___processes.

hair cells

quivering bundles that let us hear

rods

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

nociceptors

sensory receptors that detect hurtful temperatures, pressure, or chemicals

grouping

the perceptual tendency to organize stimuli into coherent groups.

red - or green - sensitive cones; monochromatic; dichromatic; trichromatic

Most people with color - deficient vision are not actually "colorblind." They simply lack functioning___ or sometimes both. Their vision—perhaps unknown to them, because their lifelong vision seems normal—is ___ (one - color) or ___ (two - color) instead of___, making it impossible to distinguish the red and green

rods; cones; color

Some nocturnal animals, such as toads, mice, rats, and bats, have impressive night vision thanks to having many more____ (rods/cones) than___(rods/cones) in their retinas. These creatures probably have very poor___ (color/black and white) vision.

Moon illusion

The Moon looks up to 50 percent larger when near the horizon than when high in the sky.

wavelength

The distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission.

critical period

The effect of sensory restriction on infant cats, monkeys, and humans suggests there is a_____for normal sensory and perceptual development.

difference threshold

The minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (or jnd).

sensation

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

Gestalt psychologists used this saying to describe our perceptual tendency to organize clusters of sensations into meaningful forms or coherent groups.

What do we mean when we say that, in perception, the whole is greater than the sum of its parts?

Light waves reflect off the person and travel into your eye, where the receptor cells in your retina convert the light waves' energy into neural impulses sent to your brain. Your brain processes the subdimensions of this visual input—including depth, movement, and form—separately but simultaneously. It interprets this information based on previously stored information and your expectations into a conscious perception of your friend.

What is the rapid sequence of events that occurs when you see and recognize a friend?

Sensation is the bottom-up process by which the physical sensory system receives and represents stimuli. Perception is the top-down mental process of organizing and interpreting sensory input.

What is the rough distinction between sensation and perception?

(1) You are expecting a text message. (2) It is important that you see the text message and respond. (3) You are alert.

What three factors will make it more likely that you correctly detect a text message?

place.

____theory presumes that we hear different pitches because different sound waves trigger activity at different places along the cochlea's basilar membrane. Thus, the brain determines a sound's pitch by recognizing the specific place (on the membrane) that is generating the neural signal. It can explain how we hear high - pitched sounds but not low - pitched sounds.

sensorineural hearing loss

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

conduction hearing loss

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

perceptual limitations

researchers have outfitted infant kittens and monkeys with goggles through which they could see only diffuse, unpatterned light. After infancy, when the goggles were removed, these animals exhibited____ much like those of humans born with cataracts. They could distinguish color and brightness, but not the form of a circle from that of a square.

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.

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.

relative luminance

the amount of light an object reflects relative to its surroundings. White paper reflects 90 percent of the light falling on it; black paper, only 10 percent. Although a black paper viewed in sunlight may reflect 100 times more light than does a white paper viewed indoors, it will still look black. But if you view sunlit black paper through a narrow tube so nothing else is visible, it may look gray, because in bright sunshine it reflects a fair amount of light.View it without the tube and it is again black,because it reflects much less light than the objects around it.

sensory interaction

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

accommodation

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

vestibular sense; inner ear

the sense of body movement and position, including the sense of balance. The biological gyroscopes for this sense of equilibrium are in your ___.

lens

the transparent structure behind the pupil that changes shape to help focus images on the retina.

perceptual set

A mental predisposition to perceive one thing and not another. A set of mental tendencies and assumptions that greatly affects (top - down) what we perceive.

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.

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.

receive; transform; deliver

All our senses • ___ sensory stimulation, often using specialized receptor cells. • ___ that stimulation into neural impulses. • ___the neural information to your brain.

bottom - up processing

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

subliminal

Below one's absolute threshold for conscious awareness. (Stimuli you cannot detect 50 percent of the time).

freedom to focus on informative changes in our environment without being distracted by background chatter. We perceive the world not exactly as it is, but as it is useful for us to perceive it.

Benefit of sensory adaption?

transduction

Conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.

sensory adaptation

Diminished sensitivity as a consequence of constant stimulation.

It involves top-down processing. Our perceptual set influences our interpretation of stimuli based on our experiences, assumptions, and expectations.

Does perceptual set involve bottom-up or top-down processing? Why?

less

Emotions color our social perceptions, too. Spouses who feel loved and appreciated perceive ___ threat in stressful marital events

We are normally able to perceive depth thanks to the binocular cues that are based on our retinal disparity, and monocular cues including relative height, relative size, interposition, linear perspective, light and shadow, and relative motion.

How do we normally perceive depth?

We have two types of retinal receptors, four basic touch senses, and five taste sensations. But we have no basic smell receptors. Instead, different combinations of odor receptors send messages to the brain, enabling us to recognize some 10,000 different smells.

How does our system for sensing smell differ from our sensory systems for vision, touch, and taste?

more; sooner; locating sounds

If a car to the right honks, your right ear receives a___intense sound, and it receives sound slightly___ than your left ear. people who lose all hearing in one ear often have difficulty ____.

Interposition

If one object partially blocks our view of another, we perceive it as closer. The depth cues provided by interposition make this an impossible scene.

Relative size

If we assume two objects are similar in size, most people perceive the one that casts the smaller retinal image as farther away.

Absolute threshold is the minimum stimulation needed to detect a particular sound (such as an approaching bike on the sidewalk behind us) 50 percent of the time. Subliminal stimulation happens when, without our awareness, our sensory system processes that sound (when it is below our absolute threshold). A difference threshold is the minimum difference for us to distinguish between two sounds.

Illustrate, using sound, the distinctions among these concepts: absolute thresholds, subliminal stimulation, and difference thresholds.

Context Effects

Imagine hearing a noise interrupted by the words "eel is on the wagon." Likely, you would actually perceive the first word as wheel. Given "eel is on the orange," you would hear peel. ____ phenomenon, discovered by Richard Warren, suggests that the brain can work backward in time to allow a later stimulus to determine how we perceive an earlier one.

retina's neural layers; bipolar cells; ganglion cells;

Information processing begins in the____, which are actually brain tissue that has migrated to the eye during early fetal development. After processing by your retina's nearly 130 million receptor rods and cones, information travels to your___ , then to your million or so ___, and through their axons making up the optic nerve to your brain. Any given retinal area relays its information to a corresponding location in the visual cortex, in the occipital lobe at the back of your brain

top - down processing

Information processing guided by higher - level mental processes, as when we construct perceptions drawing on our experience and expectations. Or constructs perceptions from the sensory input by drawing on our experience and expectations.

cornea; pupil; iris; lens; retina; accommodation.

Light enters the eye through the___, which protects the eye and bends light to provide focus. The light then passes through the ___, a small adjustable opening. Surrounding the pupil and controlling its size is the___, a colored muscle that dilates or constricts in response to light intensity and even to inner emotions. Each iris is so distinctive that an iris-scanning machine can confirm your identity. Behind the pupil is a ___ that focuses incoming light rays into an image on the ___, a multilayered tissue on the eyeball's sensitive inner surface. The lens focuses the rays by changing its curvature in a process called___.

Light and shadow

Shading produces a sense of depth consistent with our assumption that light comes from above.

Afterimage effect

Stare at a green square for a while and then look at a white sheet of paper, and you will see red, green's opponent color. Stare at a yellow square and its opponent color, blue, will appear on the white paper. This is ___ effect.

hot; burning hot

Stroking adjacent pressure spots creates a tickle.Repeated gentle stroking of a pain spot creates an itching sensation. Touching adjacent cold and pressure spots triggers a sense of wetness, which you can experience by touching dry, cold metal. Stimulating nearby cold and warm spots produces the sensation of____. When ice - cold water passes through one coil and comfortably warm water through another, we perceive the combined sensation as ___.

priming

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

pupil

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

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.

loudness; pitch; low; high

The amplitude of sound waves determines their ___. Their length, or frequency, determines the___ we experience. Long waves have___frequency—and low pitch. Short waves have ___frequency—and high pitch.

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. (the color we experience, such as the tulip's red petals or green leaves)

absolute threshold

The minimum stimulation needed to detect a particular stimulus (light, sound, pressure, taste, or odor) 50 percent of the time.

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). This law states that for an average person to perceive a difference, two stimuli must differ by a constant proportion (not a constant amount). Two lights, for example, must differ in intensity by 8 percent. Two objects must differ in weight by 2 percent. And two tones must differ in frequency by only 0.3 percent.

perception

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

higher; wave amplitude.

The shorter the wavelength, the____ the frequency. _____determines the intensity of colors.

psychophysics

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

visual cortex

To recognize a face, your brain integrates information projected by your retinas to several ___ areas, compares it to stored information, and enables you to recognize the face.

Closure

We fill in gaps to create a complete, whole object. Thus we assume that the circles on the left are complete but partially blocked by the (illusory) triangle. Add nothing more than little line segments to close off the circles and your brain stops constructing a triangle.

Proximity

We group nearby figures together. We see not six separate lines, but three sets of two lines.

Relative height

We perceive objects higher in our field of vision as farther away. Because we assume the lower part of a figure-ground illustration is closer, we perceive it as figure

Continuity

We perceive smooth, continuous patterns rather than discontinuous ones. This pattern could be a series of alternating semicircles, but we perceive it as two continuous lines—one wavy, one straight.

The outer ear collects sound waves, which are translated into mechanical waves by the middle ear and turned into fluid waves in the inner ear. The auditory nerve then translates the energy into electrical waves and sends them to the brain, which perceives and interprets the sound.

What are the basic steps in transforming sound waves into perceived sound?

The Young-Helmholtz trichromatic theory shows that the retina contains color receptors for red, green, and blue. The opponent-process theory shows that we have opponent-process cells in the retina for red-green, yellowblue, and white-black. These theories are complementary and outline the two stages of color vision: (1) The retina's receptors for red, green, and blue respond to different color stimuli. (2) The receptors' signals are then processed by the opponent-process cells on their way to the visual cortex in the brain.

What are two key theories of color vision? Are they contradictory or complementary? Explain.

The shoes provide constant stimulation. Sensory adaptation allows us to focus on changing stimuli.

Why is it that after wearing shoes for a while, you cease to notice them (until questions like this draw your attention back to them)?

Cones; Rods; cones; rods.

___ also enable you to perceive color. In dim light they become ineffectual, so you see no colors. ____, which enable black - and - white vision, remain sensitive in dim light. Several rods will funnel their faint energy output onto a single bipolar cell. Thus, cones and rods each provide a special sensitivity—___ to detail and color, and ___ to faint light.

Signal detection

___ theorists seek to understand why people respond differently to the same stimuli, and why the same person's reactions vary as circumstances change. Exhausted parents will notice the faintest whimper from a newborn's cradle while failing to notice louder, unimportant sounds. Lonely, anxious people at speed-dating events also respond with a low threshold, and thus tend to be unselective in reaching out to potential dates.

Cones;Rods.

___cluster in and around the fovea, the retina's area of central focus. Many have their own hotline to the brain: Each one transmits to a single bipolar cell that helps relay the cone's individual message to the visual cortex, which devotes a large area to input from the fovea. ___have no such hotline; they share bipolar cells with other rods, sending combined messages.

retinal disparity; closer

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___ the object.

cochlear implant

a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea. The implants will not enable normal hearing in adults if their brain never learned to process sound during childhood.

phantom sounds

a ringing - in - the - ears sensation known as tinnitus.

pitch

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

phi phenomenon

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

gestalt

an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes. The whole may exceed the sum of its parts.

context

brightness constancy (also called lightness constancy) depends on___.

10,000

decibels, with zero decibels representing the absolute threshold for hearing. Every 10 decibels correspond to a tenfold increase in sound intensity. Thus, normal conversation (60 decibels) is ___ times more intense than a 20-decibel whisper.

monocular cues

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

binocular cues

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

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.

embodied cognition

in psychological science, the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments. It illustrates how brain circuits that process our bodily sensations connect with brain circuits responsible for cognition.

perceptual adaptation

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

feature detectors

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

place; frequency ;volley principle

neural cells can alternate firing. By firing in rapid succession, they can achieve a combined frequency above 1000 waves per second. Thus, ___ theory best explains how we sense high pitches, ___theory best explains how we sense low pitches, and some combination of place and frequency seems to handle the pitches in the intermediate range. _____principle.

biopsychosocial

our perception of pain is a ____phenomenon.

color constancy

perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object.

precognition

perceiving future events, such as an unexpected death in the next month.

perceptual constancy

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

clairvoyance

perceiving remote events, such as a house on fire in another state.

fovea

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

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.

extrasensory perception (ESP)

the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition.

inner ear

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

retina

the light - sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information.

optic nerve

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

frequency

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

figure - ground

the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground). Among the voices you hear at a party, the one you attend to becomes the figure; all others are part of the ground. As you read, the words are the figure; the white paper is the ground.

blind spot

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

parallel processing

the processing of many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision. Contrasts with the step - by - step (serial) processing of most computers and of conscious problem solving.

audition

the sense or act of hearing. We hear a wide range of sounds, but the ones we hear best are those sounds with frequencies in a range corresponding to that of the human voice.

parapsychology

the study of paranormal phenomena, including ESP and psychokinesis.

kinesthesis [kin - ehs - THEE-sehs]

the system for sensing the position and movement of individual body parts.

opponent - process theory

the theory that opposing retinal processes (red - green, yellow - blue, white - black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green.

Young - Helmholtz trichromatic (three - color) theory; red; green

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. Any color can be created by combining the light waves of three primary colors—red, green, and blue. When we stimulate combinations of these cones, we see other colors. For example, there are no receptors especially sensitive to yellow. We see yellow when mixing__ and __light, which stimulates both red -sensitive and green - sensitive cones.

gate - 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. The "gate" is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.

interpretation

we even organize a string of letter —THEDOGATEMEAT—into words that make an intelligible phrase, more likely "The dog ate meat" than "The do gate me at". This process involves not only the organization we've been discussing, but also____—discerning meaning in what we perceive.

size constancy

we perceive objects as having a constant size, even while our distance from them varies.

shape constancy;

we perceive the form of familiar objects, such as the door in FIGURE 6.33, as constant even while our retinas receive changing images of them.

synaesthesia

where one sort of sensation (such as hearing sound) produces another (such as seeing color).