psychology units 3+4 review

Sensation

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

Bottom-up Processing

analysis that begins with 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

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 (noise). Assumes there is no single absolute threshold and that detection depends partly on a person's experience, expectations, motivation, and level of fatigue

Subliminal

below one's absolute threshold for conscious awareness

Priming

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

Difference Threshold

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

Weber's Law

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

Sensory Adaptation

diminished sensitivity as a consequence of constant stimulation

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 brains can interpret.

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

Hue

the dimension of color that is determined by the wavelength of light; what we know as the color names, blue, green. etc

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

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

Retina

the light-sensitive inner surface of the eye, containing the receptor rods and coned plug 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, and gray; necessary for peripheral and twilight vision, when cones don't respond

Cones

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

Optic Nerve

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

Blind Spot

the point at which the optic nerve leaves the eye. No receptor cells are located there

Fovea

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

Feature Detectors

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

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.

Young-Helmholtz trichromatic (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

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

Audition

the sense or act of hearing

Frequency

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

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 windows

Cochlea

a coiled, bony fluid-filled the 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.

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 nerves impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch

Conduction Hearing Loss

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

sensorineural Hearing loss

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

Cochlear Implant

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

Kinesthesis

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

Vestibular Sense

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

Gate-Control Theory

the theory that the spinal cord contains a neurological "gate" that clocks 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.

Sensory Interaction

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

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 that stand out from their surrounding

Grouping

the perceptual 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 laboratory device for testing depth perception in infants and young animals

Binocular Cues

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

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 Cues

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

Phi Phenomenon

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

Perceptual Constancy

Perceiving objects as unchanging (having consistent shapes, size, lightness, and color) even as illumination and 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

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

Perceptual Set

a mental predisposition to perceive one thing and not another.

Bipolar Cells

part of the eye activated when light energy triggers chemical changes to spark neural signals, which then activate ganglion cells

Ganglion Cells

activated by bipolar cells in the eye, these axons twine together to form strands of the optic nerve

Pathway to the visual cortex

ganglion axons forming the optic nerve run to the thalamus, where they synapse with neurons that run to the visual cortex

Color-Blind vision

people may suffer from red-green deficiency or have trouble with perception of a number within a design.

Proximity

grouping nearby figures together

continuity

grouping smooth continuous patterns rather than discontinuous ones

closure

filling in gaps to create a complete, whole object

Relative luminance or Relative brightness or Light & Shadow

the amount of light an object reflects relative to its surroundings

connectedness

Gestalt grouping principle; when objects uniform (in color or texture) are linked (no space exists between them) we perceive them as a single unit

similarity

the tendency to perceive things that look alike as being part of the same group

linear perspective

A monocular cue for perceiving depth; the more parallel lines converge, the greater their perceived distance.

relative height

we perceive objects higher in our field of vision as farther away

relative size

a monocular cue for perceiving depth; the smaller retinal image is farther away

interposition

if one object partially blocks our view of another, we perceive it as closer

texture gradient

a monocular cue for perceiving depth; a gradual change from a coarse distinct texture to a fine, indistinct texture signals increasing distance. objects far away appear smaller and more densely packed

relative clarity

a monocular cue for perceiving depth; hazy objects are farther away than sharp, clear objects

learning

any relatively permanent change in behavior due to experience

associative learning

when organisms learn that two certain events occur together. two variations of associative learning are classical conditioning and operant conditioning

classical conditioning

learning in which a neutral stimulus becomes capable of triggering a conditioned response after having become associated with an unconditioned stimulus

behaviorism

The view that psychology should be an objective science that studies behavior without reference to mental processes; Watson.

unconditioned response

In classical conditioning, the unlearned, naturally occurring response to the unconditioned stimulus (US), such as salivation when food is in the mouth.

unconditioned stimulus

the stimulus that naturally and automatically triggers the reflexive unconditioned response

conditioned response

the learned response to previously neutral conditioned stimulus, which results from the acquired association between CS and US

conditioned stimulus

an originally neutral stimulus that comes to trigger a CR after association with an US

acquisition

the initial stage of conditioning in which the new response is established and gradually strengthened.

the strengthening of a reinforced response (operant)

extinction

weakening of a CR when the CS is no longer followed by the US;

operant- when the behaviour is no longer reinforced

spontaneous recovery

the reappearance, after a pause, of an extinguished conditioned response

generalization

The tendency, once a response has been conditioned, for stimuli similar to the conditioned stimulus to elicit similar responses.

discrimination

the ability to distinguish the CS from similar stimuli that do not signal a US

operant conditioning

A type of learning in which behavior is strengthened if followed by a reinforcer or diminished if followed by a punisher.

respondent behavior

behavior that occurs as an automatic response to some stimulus; Skinner's term for behavior learned through classical conditioning

operant behavior

behavior that operates on the environment, producing consequences

law of effect

Thorndike's principle that behaviors followed by favorable consequences become more likely, and that behaviors followed by unfavorable consequences become less likely

operant chamber

in operant conditioning research, a chamber (also known as a Skinner box) containing a bar or key that an animal can manipulate to obtain a food or water reinforcer; attached devices record the animal's rate of bar pressing or key pecking.

shaping

operant conditioning; procedure for establishing a new response by reinforcing successive approximations of the desired behaviour.

reinforcer

any event that strengthens the behavior it follows

positive reinforcement

Presentation of a stimulus after a particular response in order to increase the likelihood that the response will recur

negative reinforcement

Removal of an aversive stimulus after a particular response to increase the likelihood that the response will recur

primary reinforcers

In and of themselves, rewarding things. (food, water, rest.) Natural properties are rewarding.

conditioned reinforcers

learned reinforcers, such as money, that develop their reinforcing properties because of their association with primary reinforcers