AP Psych Unit 4 - Sensation and Perception (Myers Textbook)

Sensation

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

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

Selective Attention

The focusing of conscious awareness on a particular stimuli

Cocktail Party Effect

Your ability to attend to only one voice among many (while also being able to detect your own name in an unattended voice)

Inattentional Blindness

Failing to see visible objects when our attention is directed elsewhere

Change Blindness

Exploited by magicians; the failing to notice changes in our environment

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 that our brain can interpret

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% of the time

Signal Detection Theory

A theory predicting how and when we detect the presence of a faint simulus (signal) amid background stimulation (noise); assumes that there is no single absolute threshold and that detection depends partially on a person’s experience, expectations, motivation, and alertness

Subliminal

Below one’s absolute threshold for conscious awarness

Priming

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

Difference Threshold

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

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 Adaptation

Diminished sensitivity as a consequence of constant stimulation (The more we are exposed to something, the less aware we become of it because our nerve cells fire less frequently); gives us the freedom to focus on information changes in our environment without being distracted by background chatter

Perceptual Set

A mental predisposition to perceive one thing and now another; can influence what we hear, taste, feel, and see

Extrasensory Perception (ESP)

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

Parapsychology

The study of paranormal phenomena, including ESP and psychokinesis

Wavelength

The distance from the peak of the 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

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 amplitude

Cornea

Protects the eye and bends light to provide focus; light enters the eye through it first

Pupil

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

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

Lens

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

Accommodations

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 grey; necessary for peripheral and twilight, when cones don’t respond

Cones

Retinal receptors 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; made up of bipolar ad ganglion cells

Blind Spot

The point at which the optic nerve leaves the eye, creating a “blind spot” because no receptors cells are located thereFor

Forea

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

Feature Detectors

Nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement; receive information from individual ganglion cells

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 (senal) processing of most computers and of conscious problem solving

Young-Helmholtz Trichromatic (three-color-theory)

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

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; occurs in two stages 1) Retina’s red, green, blue cones respond in varying degrees to color stimuli 2) Signals are processed by the nervous system’s opponent-process cells

Gestalt

An organized whole; Gestalt psychologists emphasized our tendency to integrate pieces of information into a visual whole

Figure-Ground

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

Grouping

The perceptual tendency to organize stimuli into coherent groups

Proximity

Grouping nearby objects together

Continuity

Perceiving smooth, continuous pattern over discontinuous ones

Closure

Filling in gaps to create a complete, whole object

Depth Perception

The ability to see objects in 3D although the images that strike the retina are 2D; allow us to judge distance

Visual Cliff

A laboratory device for testing depth perception in infants and young animals, designed by Eleanor Gibson

Retinal 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

Monocular Cue

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

Stroboscopic Movement

When the brain perceives continuous movement in a rapid series of slightly varying images, such as in film animation

Phi Phenomenon

An illusion of movement created when two or more adjacent lights blink on and off in a quick sequence

Relative Height

A monocular depth cue; perceiving objects higher in our field of vision as father (ex. lower = ground, higher= sky)

Relative Size

A monocular depth cue; if we assume two objects are similar size, most people perceive the smaller retinal image as further

Interposition

A monocular depth cue; if one object partially blocks out view of another, we perceive it as closer

Relative Motion

A monocular depth cue; as we move, objects that are actually stable may appear to move

Linear Perspective

A monocular depth cue; parallel lines in the distance appear to meet

Light & Shadow

A monocular depth cue; shading produces a sense of depth because we assume light comes from above

Perceptual Constancy

Perceiving objects as unchanging (have consistent shape, size, brightness, and color) even as illumination and retinal image change

Color Constancy

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

Relative Luminance

The amount of light an object reflects relative to its surroundings

Shape Constancy

We perceive the form of familiar objects

Size Constancy

We perceive objects as having a constant size, even when our distance from it varies

Perceptual Adaption

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

Audition

The sense or act of hearing

Frequency

The number of complete wavelengths that pass a point in a given time

Pitch

A tone’s experienced highness or lowness; depends on frequency

Middle Ear

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

Cochlea

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

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

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

Cochlear Implant

The only way to restore hearing for people with nerve deafness; a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

Place Theory

Hermann Von Helmholtz’s; 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 the nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

Volley Principle

Theory that handles pitches intermediate range; neural cells can alternate firing and by firing in rapid succession, can achieve a combined frequency

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; by Ronald Melzack and Patrick Wall

The Pain Circuit

Sensory receptors (nociceptors) respond to potentially damaging stimuli by sending an impulse to the spinal cord, which passes the message to the brain, which interprets the signal aspain \*

Unami

The savory meat taste of the flavor enhanced MSG, often found in Chinese and Thai food

Kinesthesia

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

Vestibular Sense

The sense of body movements and position, including the sense of balance

Sensory Interactions

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

McGurk Effect

When senses disagree, we may perceive a third syllable that blends both inputs

Embodied Cognition

In psychological science, the influence of bodily sensations, gestures, and other states on cognitive preferences and judgement

Synesthesia

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