Psych unit 2

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.

Perception

The process by which our brain organizes and interprets sensory information, enabling us to recognize objects and events as meaningful.

Bottom up processing

Information processing 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.

Transduction

Conversion of one form of energy into another; the transforming of physical energy into neural impulses our brain can interpret.

Absolute threshold

The minimum stimulus energy needed to detect a particular stimulus 50% of the time.

Signal detection theory

Predicts how and when we detect the presence of a faint stimulus amid background stimulation.

Subliminal

Below one's absolute threshold for conscious awareness.

Difference threshold

The minimum difference between two stimuli required for detection 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.

Sensory adaptation

Diminished sensitivity as a consequence of constant stimulation.

Perceptual set

A mental predisposition to perceive one thing and not another.

Wavelength

The distance from the peak of one light wave or sound wave to the peak of the next.

Hue

The dimension of color that is determined by the wavelength of light.

Intensity

The amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness.

Retina

The light-sensitive back 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, and gray, and are sensitive to movement, necessary for peripheral and twilight vision.

Cones

Retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions.

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 eye's cones cluster.

Young-Helmholtz trichromatic theory

The theory that the retina contains three different types of color receptors—one most sensitive to red, one to green, and one to blue.

Opponent-process theory

The theory that opposing retinal processes (red-green, blue-yellow, white-black) enable color vision.

Feature detectors

Nerve cells in the brain's visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement.

Parallel Processing

Processing multiple aspects of a stimulus or problem simultaneously.

Gestalt

An organized whole.

Figure-ground

The organization of the visual field into objects that stand out from their surroundings.

Grouping

The perceptual tendency to organize stimuli into coherent groups.

Depth perception

The ability to see objects in three dimensions, allowing us to judge distance.

Visual cliff

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

Binocular cues

A depth cue that depends on the use of two eyes.

Retinal disparity

A binocular cue for perceiving depth by comparing retinal images from the two eyes.

Monocular cue

A depth cue 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 and retinal images change.

Perceptual adaptation

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

Audition

The sense or act of hearing.

Frequency (measured in hertz)

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

Pitch

A tone's experienced highness or lowness.

Middle ear

The chamber between the eardrum and cochlea containing three tiny bones that concentrate the vibrations.

Cochlea

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

Inner ear

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

Sensorineural hearing loss

The most common form of hearing loss, caused by damage to the cochlea's receptor cells or to the auditory nerve.

Conduction hearing loss

The 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.

Place theory (coding)

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

Frequency theory (temporal coding)

In hearing, the theory that the rate of nerve impulses matches the frequency of a tone, thus enabling us to sense its pitch.

Gate control theory

The theory that the spinal cord contains a neurological gate that blocks pain signals or allows them to pass to the brain.

Hypnosis

A social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur.

Dissociation

A split in consciousness that allows some thoughts and behaviors to occur simultaneously with others.

Posthypnotic suggestions

A suggestion made during a hypnosis session to be carried out after hypnosis.

Gustation

Sense of taste.

Olfaction

Sense of smell.

Kinesthesia

Our movement sense; our system for sensing the position and movement of individual body parts.

Vestibular sense

Our balance sense; our sense of body movement and position that enables our sense of balance.

Sensory interaction

The principle that one sense can influence another.

Embodied cognition

The influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.

Extrasensory perception

The controversial claim that perception can occur apart from sensory input.

Parapsychology

The study of paranormal phenomena, including ESP and psychokinesis.

Memory

The persistence of learning over time through encoding, storage, and retrieval of info.

Recall

A measure of memory in which the person must retrieve information learned earlier.

Recognition

Identifying items previously learned.

Relearning

Learning something more quickly when you learn it again.

Encode

The process of getting information into the memory system.

Store

Retention of encoded information.

Retrieve

The process of getting information out of memory storage.

Parallel processing

Processing multiple aspects of a stimulus or problem simultaneously.

Sensory memory

The immediate, very brief recording of sensory information in the memory system.

Short term memory

Briefly activated memory of a few items that is later stored or forgotten.

Long term memory

The relatively permanent and limitless archive of the memory systems.

Working memory

A newer understanding of short-term memory that involves conscious, active processing of both incoming sensory info and previously stored info.

Explicit (declarative) memories

The retention of facts and experiences that we can consciously know and declare.

Effortful processing

Encoding that requires attention and conscious effort.

Automatic processing

Unconscious encoding of incidental information.

Implicit (nondeclarative) memories

Retention of learned skills or conditioned associations independent of conscious recollection.

Iconic memory

A momentary sensory memory of visual stimuli.

Echoic memory

A momentary sensory memory of auditory stimuli.

Chunking

Organizing items into familiar, manageable units.

Mnemonics

Memory aids, especially techniques that use vivid imagery and organizational devices.

Spacing effect

The tendency for distributed study or practice to yield better long-term retention.

Testing effect

Enhanced memory after retrieving rather than simply rereading information.

Shallow processing

Encoding on a basic level, based on the structure or appearance of words.

Deep processing

Encoding semantically based on the meaning of words; yields the best retention.

Semantic

Explicit memory of facts and general knowledge.

Episodic

Explicit memory of personally experienced events.

Hippocampus

A neural center located in the limbic system that helps process explicit memories for storage.

Memory consolidation

The neural storage of a long-term memory.

Flashbulb memories

A clear memory of an emotionally significant moment or event.

Long-term potentiation

An increase in a nerve cell’s firing potential after brief, rapid stimulation.

Priming

The activation, often unconsciously, of certain associations.

Encoding specificity principle

The idea that cues and contexts specific to a memory will be most effective in helping us recall it.

Serial position effect

Our tendency to recall best the last and first items in a list.

Mood congruent

The tendency to recall experiences consistent with one's current mood.

Anterograde amnesia

An inability to form new memories.

Retrograde amnesia

An inability to remember information from one's past.

Proactive interference

The forward-acting disruptive effect of older learning on the recall of new information.

Retroactive interference

The backward-acting disruptive effect of newer learning on the recall of old information.

Repress

In psychoanalytic theory: the basic defense mechanism that banishes from consciousness anxiety-arousing thoughts.