AP Psych Modules 16-21

Sensation

Sensation

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

Sensory Receptors

•  Sensory nerve endings that respond to stimuli

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 we construct perceptions drawing on our experience and expectations

Selective Attention

The focusing of conscious awareness on a particular stimulus

Inattentional Blindness

Failing to see visible objects when our attention is directed elsewhere

Change Blindness

Failing to notice changes in the environment, a form of inattentional blindness 

Transduction

 Conversion of one form of energy to another. In sensation, the transforming stimulus energies, such as lights, sounds, and smells, into neural impulses 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 stimulus energy 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 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% of the time. We experience the difference threshold as just a noticeable difference

Priming

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

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 

Perceptual Set

A mental predisposition to perceive one thing and not the other

Extrasensory perception

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

Parapsychology

• The study of paranormal phenomena, including ESP and psychokinesis (moving things with you mind)

Wavelength

The distance from the peak of one light or sound wave to the next. Electromagnetic wavelengths vary from short blips of gamma rays to 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 wave or sound wave, which influences what we perceive as brightness or loudness. Intensity is determined by the waves amplitude (height)

Cornea

• The eye’s clear, protective outer layer, covering the pupil and iris

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 pupil opening 

Lens

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

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

Accommodation

• 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, gray, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond

Cones

• Retinal receptors that are concentrated near the center of the retina and that function in daylight or well lit conditions. Cones detect fine detail and give rise to color sensations 

Optic nerve

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

Blind spot

• 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 eyes cones cluster

Young-Helmholtz trichromatic (three-color) Theory

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

Opponent process theory

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

Feature Detectors

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

Parallel Processing

•  Processing many aspects of a problem simultaneously; the brain's natural mode of information processing for many functions, including vision

Gestalt

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

Figure-ground

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

Grouping

•  The perceptual tendency to organize stimuli into coherent groups 

Depth Perception

• The ability to see objects in 3 dimensions although the images strike the retina as 2-Dimensional, allows us to judge distance

Visual Cliff

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

Binocular Cue

• A depth cue, such as retinal disparity, that depends on the use of 2 eyes

Retinal Disparity

• A binocular cue for perceiving depth. By comparing retinal images from the two eyes, the brain computes distance- the greater disparity between the two objects images, the closer the object

Monocular Cues

• A depth cue, such as an interposition or linear perspective, available to either eye alone

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 or retinal images change

Color Constancy

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

Perceptual adaptation

• The ability to adjust to changed sensory input, including an artificially displaced or inverted visual field

Auditation

• The sense or act of hearing 

Frequency

• The number of complete wavelengths that pass a point in a given time (Ex. Per Sec)

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 

Cochlea

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

Inner Ear

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

Sensorineural hearing loss

• Hearing loss caused by damage to the cohela’s receptor cells or to study the auditory nerves; the cells most common for of hearing loss, also called nerve deafness 

Conduction hearing loss

• A less common form of hearing loss, caused by damage to the mechanical system that conducts sound waves to the cochlea

Cochlear implant

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

Place Theory

• In hearing, the theory that link the pitch we hear with the place where the cochlea's membrane is stimulated 

Frequency Theory

• In hearing, the theory that the heart rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch (temporal theory)

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 the small nerve fibers and is closed by the activity in large fibers or information coming from the brain 

Olfaction

• The sense of smell

Kinesthesia

• Our movement sense- our system for sensing the position and movement of individual body parts 

Vestibular Sense

• Our sense of body movement and position that enables our sense of balance

Sensory Interaction

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

Embodied Cognition

• The influence of bodily sensations, gestures, and other states on cognitive preferences and judgements