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Glossary 2
Glossary Of Terms M-Z For Introduction to Psychology
magnetic resonance imaging (MRI) - Imaging technique that involves the use of radio waves and a strong magnetic field to produce a signal that can be interpreted by a computer
maintenance rehearsal - Rehearsal used when we want to save or maintain a memory for a specified period of time
mania - Excessive activity, accelerated speech, poor judgment, and euphoria; symptoms of bipolar disorder
manifest content - According to Freud, the dream as reported by the dreamer
marijuana - Substance derived from the Cannabis sativa plant
maturation - Biological unfolding of the genetic plan for an individual's development
medical model - The view that mental disorders are like physical illnesses and have underlying organic causes
medulla - Structure located in the hindbrain that regulates automatic responses such as breathing, swallowing, and blood circulation
meiosis - Type of cell division that results in a reduction of the amount of genetic material in each of the resulting cells
memory - System or process by which the products or results of learning are stored for future use
menarche - Beginning of menstruation
menopause - Cessation of ovulation and menstruation; these changes mark the end of the childbearing years
mental age - Measure of intelligence derived by comparing an individual's score on an intelligence test with the average performance of individuals of the same age
method of loci - Use of familiar locations as cues to recall items that have been associated with them
microvilli - Hairs that project from taste receptors
midbrain - Major division of the brain that contains fibers known as the reticular formation
middle adulthood - Period from approximately age 40 to age 65
midlife crisis - Potentially stressful period that occurs during the mid-forties and is triggered by reevaluation of one's accomplishments
mitosis - Process of cell division in which each cell contains the same genetic information as other cells
mnemonic devices - Procedures for associating new information with previously stored memories
model - Framework that is helpful in understanding a particular phenomenon
monochromat - Individual who sees only shades of gray due to a rare form of colorblindness
monocular cues - Cues for depth perception that involve the use of only one eye
mood disorders - Extremes of emotional levels such as unipolar depression and bipolar disorder
moratorium - Period during which an adolescent may try several identities without intending to settle on a specific one
Moro reflex - Startle reflex in response to a loud noise or the sensation of being dropped
Morpheme - The smallest unit of language that has meaning
multiple sclerosis - Disease caused by degeneration of myelin in the central nervous system
myelin sheath - Fatty protein substance that covers some axons, increasing speed of transmission
narcolepsy - Sleep disorder characterized by excessive daytime sleepiness and cataplectic attacks induced by emotion; the symptoms are due to the intrusion of REM sleep into waking time
natural selection - The principle that the strongest or most fit organisms are the ones that adapt best to their environment
naturalistic observation - Study of behavior in its typical setting, with no attempt to alter it
nature - Theory that holds that physical and cognitive development is genetically determined
negative identity - Adoption of behaviors that are the opposite of what is expected
negative reinforcer - Event that is removed after the target response, thereby increasing the likelihood that this response will occur again
negative transfer - Condition in which previous learning interferes with subsequent learning
neuromodulators - Chemicals that may have a widespread or general effect on the release of neurotransmitters
neurons - Basic cells of the nervous system
neuropsychologist - Psychologists trained in the diagnosis and rehabilitation of brain disorders
neurotransmitters - Chemical substances, stored in the terminal buttons, that facilitate the transmission of information from one neuron to another
neutral stimulus (NS) - Stimulus that, before conditioning, does not elicit a particular response
nightmare - Frightening dream that occurs during REM sleep
nodes of Ranvier - Gaps in the myelin sheath
non-REM (NREM) sleep - Stages of sleep other than REM sleep (Stages 1, 2, 3, and 4); NREM sleep consists primarily of Stages 3 and 4 early in the night and Stage 2 later on
nonsense syllables - Stimuli used to study memory, typically composed of a consonant-vowel-consonant sequence
nonverbal communication - Communication that involves movements, gestures, and facial expressions
normal curve - Symmetrical, bell-shaped distribution of scores or attributes in which the majority of scores are clustered around the mean
norms - Distribution of scores obtained by a large sample of people who have taken a particular psychological test
nurture - Theory that holds that physical and cognitive development is determined by environmental factors
obedience - Initiating or changing a behavior in response to a direct command
obesity - Body weight of 20 percent or more in excess of ideal body weight
object permanence - Recognition that objects continue to exist even though they cannot be directly sensed
observational learning (social learning theory) - Learning that occurs through watching and imitating the behaviors of others
obsessive-compulsive disorder (OCD) - An anxiety disorder characterized by repetitive, irrational, intrusive thoughts, impulses, or images (obsessions) and irresistible impulses (compulsions) to engage repeatedly in some act such as checking that doors are locked or washing hands
Oedipal complex - Process that occurs during the phallic stage in which a boy wishes to possess his mother sexually and fears retaliation by his father
olaction - The sense of smell
operant conditioning - Learning that occurs when the participant must make a response to produce a change in the environment
operational definition - A careful and precise definition that allows other researchers to repeat an experiment
opioid peptides - Painkillers that are produced by the body
opioids - Drugs that reduce pain
optic chiasm - Point at which the optic nerve fibers from each eye join; fibers from the nasal half of the retina cross to the opposite hemisphere of the brain
oral stage - first stage of psychosexual development in which the mouth is the focus of pleasure-seeking activity
organ of Corti - Structure located on the basilar membrane of the inner ear that contains the auditory receptors
osmotic thirst - Thirst created by a depletion of intracellular fluids
ossicles - Three bones (hammer, anvil, and stirrup) located in the middle ear that conduct sound from the outer to the inner ear
osteoporosis - Condition in which the bones become thinner and more prone to fractures and breaks; typically appears in women following menopause
oval window - Structure that connects the middle ear with the cochlea of the inner ear; its movement causes fluid in the cochlea to move
paired-associate learning - Learning procedure in which items to be recalled are learned in pairs. During recall, one member of the pair is presented and the other is to be recalled
panic disorder - The most severe anxiety disorder, characterized by intense physiological arousal not related to a specific stimulus
papillae - Bumps or protrusions distributed on the tongue and throat that are lined with taste buds
paralanguage - Communication that involves aspects of speech such as rate of talking and tone of voice but not the words used
paraphilia - Sexual arousal by objects or situations not considered sexual by most people
parasomnias - Sleep disorders other than insomnia and hypersomnia, which occur more frequently in children and often disappear without treatment
parasympathetic division - Subdivision of the autonomic nervous system that is responsible for returning the body to a resting or balanced state
partial reinforcement effect - Phenomenon in which extinction of an operant response following partial or intermittent reinforcement takes longer than extinction following continuous reinforcement
passionate love - Transitory form of love that involves strong emotional reactions, sexual desires, and fantasies
pattern perception - The ability to discriminate among different figures and shapes
peer group - Group of neighborhood children, classmates, or selected friends of the same age
pegword technique - Use of familiar words or names as cues to recall items that have been associated with them
perception - The process of organizing and making sense of sensory information
perceptual constancy - The tendency to perceive the size and shape of an object as constant even though its retinal image changes
perceptual hypothesis - Inference about the nature of stimuli received from the environment
perceptual illusions - Misperceptions or interpretations of stimuli that do not correspond to the sensations received
peripheral nervous system (PNS) - Division of the nervous system that consists of neural fibers lying outside the brain and spinal cord
personal fable - Feeling shared by many adolescents that one is not subject to the same rules as other people
personality - A relatively stable pattern of behaving, feeling, and thinking that distinguishes one person from another
personality disorders - Disorders characterized by long-standing, difficult-to-treat, dysfunctional behaviors that are first observed in adolescence
persuasion - The use of social influence to cause people to change attitudes or behavior
phallic stage - The third stage of psychosexual development, in which the genital organs become the focus of pleasure-seeking behavior
phencyclidine piperidine (PCP) - Powerful hallucinogen that can have unpredictable effects
pheromones - Chemicals that produce odors that elicit a particular response in members of the same species
phobia - Irrational fear of an activity, object, or situation that is out of proportion to the actual danger
phoneme - The smallest unit of sound understood as part of a language
physiological perspective - View that behaviors and mental processes can be understood and explained by studying the underlying physiology
pituitary gland - Gland located below the thalamus; called the master gland because its secretions control many other glands
place theory - Theory stating that the basilar membrane vibrates at different places to create the perception of different pitches
placebo effect - In drug research, positive effects associated with a subject's beliefs and attitudes about the drug, even when it contains no active ingredients
placenta - Organ that develops in the uterus during pregnancy; it produces hormones that maintain pregnancy, transmits nourishment to the fetus, and filters out certain harmful substances
polygenic inheritance - Principle of heredity whereby complex traits, such as intelligence and personality, are determined by many genes
polygraph - An electronic device (often called a lie detector) that senses and records changes in several physiological indices including blood pressure, heart rate, respiration, and galvanic skin response
pons - Structure of the hindbrain that connects the two halves of the brain; has nuclei that are important for sleep and arousal
positive reinforcer - Event that is presented after the target response that increases the likelihood that this response will occur again
positive transfer - Condition in which previous learning aids subsequent learning
positron emission tomography (PET) - Imaging technique that involves monitoring the metabolic activity of the brain
posttraumatic stress disorder (PTSD) - Set of symptoms that may follow deeply disturbing events; symptoms include reliving the event, difficulty in concentrating, sleep disturbances, nervousness, and guilt
precocious - Developing motor and cognitive abilities at an early age
preconventional level - Kohlberg's first stage of moral development (ages 4 to 10), in which standards set by others are observed in order to receive reinforcement or avoid punishment
prejudice - Judging a person on the basis of stereotypes about the group to which the person belongs
preoperational stage - Piaget's second stage of cognitive development, in which the child begins to think about objects that are not physically present
presbycusis - Hearing disorder involving higher frequencies that occurs in middle adulthood
presbyopia - Farsightedness that normally develops during middle adulthood; stiffening of the lens results in difficulty in focusing on near objects
prevalence - Number or percentage of individuals in a population that ever had a particular disorder during a specified period
primary appraisal - The first step in coping with stress; consists of determining whether an event is a threat
primary reinforcer - Stimulus that has innate reinforcing properties
primary sex characteristics - Characteristics directly related to reproduction
implicit memory - Unconscious memory processing in which prior exposure to stimulus items may aid in subsequent learning
proactive interference - Situation in which previously learned information hinders the recall of information learned more recently
procedural memory - Memory for making responses and performing skilled actions
progressive relaxation - Series of exercises consisting of alternately tightening and relaxing major muscle groups
projective test - Psychological test that involves the use of ambiguous stimuli in an effort to assess personality
prosocial behavior - Behavior that benefits society or helps others
proximity - Gestalt principle stating that perceptual elements that are close together are seen as a group
pseudohermaphrodite - An individual who possesses two gonads of the same kind along with the usual male or female chromosomal makeup, but has external genitalia and secondary sex characteristics that do not match his or her chromosomal makeup.
psychiatrist - Physician with specialized training in the medical treatment of mental and emotional disorders
psychic determinism - The psychodynamic assumption that all behaviors result from early childhood experiences, especially conflicts related to sexual instincts
psychoactive substances - Drugs that affect consciousness, perception, mood, and behavior
psychoanalytic therapy - Treatment of maladaptive behavior developed by Sigmund Freud; its goal is to uncover unconscious conflicts and feelings and bring them to the conscious level
psychodynamic model - The view that psychological disorders result from unconscious conflicts related to sex or aggression
psychodynamic perspective - View taken by Sigmund Freud and his followers which suggests that normal and abnormal behaviors are determined by unconscious forces
psychological therapies - Treatments for psychological disorders such as psychotherapy or therapies based on classical or operant conditioning principles
psychologist - Individual who has earned a doctoral degree and is interested in the behavior of humans and animals
psychology - Science of behavior and mental processes
psychophysiological disorders - Disorders involving physical symptoms that have been caused or worsened by psychological factors
psychosis - Any disorder in which a severely disturbed individual loses contact with reality
psychosocial crisis - Developmental problem or obstacle that is created when a psychological need conflicts with the demands of society
psychosurgery - The alteration of brain tissue in an attempt to alleviate psychological disorders
psychotherapy - A special relationship between a distressed person and a trained therapist in which the therapist aids the client in developing awareness and changing his or her thinking, feeling, and behavior
puberty - The time at which an individual achieves full sexual maturity
pubescence - Period of rapid growth, maturation of sexual organs, and appearance of secondary sex characteristics that precedes puberty
punisher - Stimulus that produces a decrease in responding; may take the form of presentation of a stimulus (positive punisher) or termination of a stimulus (negative punisher)
punishment - The process of using a punisher to decrease response rate
radiant light - Visible energy emitted by an object
random assignment - Assignment of experimental subjects to two or more groups on the basis of chance
rapid eye movement (REM) sleep - Sleep stage characterized by rapid eye movements, dreams, high brain activity, and muscle paralysis
ratio schedule - Reinforcement schedule in which reinforcement is based on the number of responses; number may be set (fixed-ratio, or FR, schedule) or may vary from one reinforcement to the next (variable-ratio, or VR, schedule)
rational-emotive therapy (RET) - A cognitive therapy in which the therapist challenges and questions the client's irrational ideas
reactance - The tendency to react in the opposite direction to a persuasive message when compliance might place limits on personal freedom
receptors - Specialized cells that are sensitive to specific types of stimulus energy
reciprocal determinism - Contention that person variables, situation variables, and behavior constantly interact
reciprocity - Tactic for increasing compliance that involves doing something for others to create a feeling of obligation on their part
recognition test - Test in which learning is measured by the ability to pick out previously learned items from a list that also contains unfamiliar items
reflected light - Light waves that are reflected from objects
reflex - Automatic behavior in response to a specific stimulus
refractory period - Brief period following an action potential when the neuron is returning to the resting state and cannot be fired
reinforcer - Event that increases the frequency of the response that it follows
reintegration - Schaie's fourth stage of cognition and thought, in which individuals in late adulthood come to grips with the meaning of their lives
relaxation response - Relaxation technique that involves the use of a mental device
relearning test - Test of learning that compares the time or trials required to learn material a second time to the time or trials required to learn the material the first time
reliability - Degree to which repeated administrations of a psychological test yield consistent scores
representative sample - Sample selected so that it reflects the characteristics of a population of interest to the researcher
representativeness heuristic - Heuristic in which one determines whether a particular instance represents a certain class or category.
repression - Defense mechanism in which anxiety-arousing ideas are pushed out of consciousness to the unconscious level of the mind
research psychologist - Psychologist whose primary activity is to conduct and report the results of experiments
resistance - A stage of psychoanalysis in which blocking of free association occurs because critical unconscious material is close to conscious awareness
resting state - Electrical charge (-70 mV) of a neuron when it is not firing
reticular formation - Nerve fibers passing through the midbrain that control arousal
retina - Tissue that contains the visual receptors, located at the back of the eye
retrieval - Third stage of the memory process, in which stored memories are brought into consciousness
retroactive interference - Situation in which information learned more recently hinders the recall of information learned previously
retrograde amnesia - Loss of memories that were stored before a traumatic event
reuptake - Method of clearing a neurotransmitter from the synaptic cleft, in which the neurotransmitter is taken back into the terminal buttons
rigidity - Tendency to rely too heavily on past experiences in solving problems
risky-shift phenomenon - The finding that groups make riskier decisions than individuals
rods - Most prevalent visual receptors; have lower threshold and lower acuity than cones and do not detect color
rooting reflex - Reflex in which the infant turns its head in the direction of a touch on its face
saturation - Trueness or accuracy of a color
savant syndrome - Case of a mentally retarded person who displays exceptional ability in a specific area
savings score - Difference between the time or trials originally required to learn material and the time or trials required to relearn the material
scatterplot - Figure that illustrates a relationship between two variables
schedule of reinforcement - Preset pattern for delivering reinforcement
schema - Grouping or cluster of knowledge about an object or sequence of events
schizophrenia - Psychotic disorder characterized by positive symptoms (excesses) such as delusions, hallucinations, and fluent but disordered speech and/or negative symptoms (deficits) such as flat or blunted affect
school psychology - Specialty of psychology that involves diagnosing and treating learning disabilities and providing consultation on other problems of school-age children
scientific method - System of investigation in which a person makes careful observations of a phenomenon, proposes theories to explain the phenomenon, makes hypotheses about future behaviors, and then tests these hypotheses through more research and observation
secondary appraisal - The second step in coping with stress; consists of deciding how to deal with the stress-producing situation
secondary reinforcer - Stimulus that acquires reinforcing properties by being associated with a primary reinforcer
secondary sex characteristics - Sex-related characteristics that develop during adolescence and are not directly related to reproduction
secular trend - Tendency of members of one generation to begin puberty at an earlier age than their parents
self-actualization - Need to develop one's full potential
self-disclosure - Personal information that an individual is willing to share
self-efficacy - An individual's expectancy concerning his or her ability to engage in effective behaviors; such expectancies differ from one behavior to another
self-fulfilling prophecy - Phenomenon whereby our expectations elicit behaviors in others that confirm our expectations
self-report inventory - Psychological tests in which individuals answer questions about themselves, usually by responding yes or no or true or false
self-serving bias - The tendency to make internal attributions when we are successful and external attributions when we fail
semantic memory - Memory for general knowledge
semantic network - Network of related concepts that are linked together
semicircular canals - Fluid-filled passages in the inner ear that detect movement of the head
sensation - Activation of receptors by stimuli in the environment
sensitization - Condition in which stimulation applied to one part of the body causes another part of the body to become more sensitive
sensorimotor stage - Piaget's first stage of cognitive development, in which children learn about their environment through direct sensory contact and motor activities
sensorineural deafness - Deafness caused by damage to the inner ear, especially the hair cells
sensory memory - Very brief but extensive memory for sensory events
serial enumeration - Ability to remember a series of events
serial learning - Learning procedure in which material that has been learned must be repeated in the order in which it was presented
serial position effect - Tendency for items at the beginning and end of a list to be learned better than items in the middle of the list
set effect - Bias toward the use of certain problem-solving approaches because of past experience
sex - Category based on biological differences in anatomy, hormones, and genetic composition
sexism - Differential treatment of an individual on the basis of his or her sex
sexual harassment - Under the law, either sexual coercion based on promised rewards or threatened punishments or creation of a hostile workplace environment
sexual orientation - Tendency for an individual to be attracted to individuals of the same sex, opposite sex, or both
shape constancy - The tendency to perceive the shape of an object as constant despite changes in its retinal image
shaping - A form of operant conditioning in which a desired response is taught by reinforcement of successive responses that more closely resemble the target response
short-term memory (STM) - Memory stage in which information is held in consciousness for 10 to 20 seconds
signal detection theory - The contention that the threshold varies with the nature of the stimulus (signal) and background stimulation (noise)
similarity - Gestalt principle stating that perceptual elements that are similar are seen as a group
simultaneous conditioning - Form of classical conditioning in which the CS and US are presented at exactly the same time
size constancy - The tendency to perceive the size of an object as constant despite changes in its retinal image
sleep apnea - Sleep disorder characterized by pauses in breathing during sleep; most prevalent in overweight males
sleep cycle - Progression of sleep stages, from Stage 1 to the end of a REM period, that repeats itself about every 90 minutes
sleep terror - Partial awakening from Stage 4 sleep characterized by loud screams and extreme physiological arousal
sleepwalking -A parasomnia that occurs during Stage 4 sleep
social facilitation - An increase in performance that occurs when other people are present
social loafing - The tendency to exert less effort when working on a group task that does not involve evaluation of individual participants
social norms - Guidelines, usually unwritten, that define behavior that is acceptable or unacceptable within a particular group
social phobia - A fear related to being seen or observed by others
social psychology - Study of the causes, types, and consequences of human interactionB
social support - Availability of comfort, recognition, approval, advice, money, or encouragement from others
sociobiology - The study of the genetic and evolutionary basis of social behavior
sociocultural model - A view that emphasizes the importance of society and culture in causing psychological disorders
soma - Cell body of a neuron
somatic division - Division of the peripheral nervous system that consists of nerves coming from the receptors to the brain and spinal cord and nerves that go to the muscles
somatization disorder - Somatoform disorder involving multiple physical complaints that do not have a medical explanation and do not suggest a specific known disease
somatoform disorders - Disorders involving physical complaints that do not have a medical cause but are related to psychological factors
somatosensory receptors - Receptors in the skin that provide sensory information
sonogram - Outline picture constructed through use of the ultrasound procedure
specific phobia - Any phobia other than agoraphobia or the social phobias, including the fear of specific animals, of elements of the natural environment, and of such things as blood, injections, or injury
spontaneous recovery - Reappearance of an extinguished CR after the passage of time
sport psychology - Specialty of psychology that provides services to athletes and coaches based on psychological principles
standardization - The development of procedures for administering psychological tests and the collection of norms that provide a frame of reference for interpreting test scores
state-dependent learning - Theory stating that when we learn something while in a specific physiological state, our recall of that information will be better when we are in the same physiological state
stereotaxic instrument - Instrument that holds a subject's head in a fixed position to allow precise surgery on subcortical structures
stereotype - Set of beliefs about members of a particular group
stimulants - Drugs that increase the activity of the central nervous system
stimulus - Environmental feature that provokes a response
storage - Second stage of the memory process, in which information is placed in the memory system. This stage may involve either brief or long-term storage of memories
stress - Nonspecific response of the body to any demand made on it
stress inoculation training - A cognitive therapy that helps clients learn ways to interpret stressful events and develop self-talk that reduces stress levels
stressor - Anything that causes an organism to adjust and display the nonspecific stress response
structuralism - Earliest approach in modern psychology, founded by Wundt; its goal was to analyze the basic elements of conscious experience
subcortical structures - Structures of the forebrain, such as the amygdala, hypothalamus, and thalamus, that are located beneath the cerebral cortex
subliminal - Below the level of conscious awareness
substance abuse - Pattern of substance use that has detrimental effects on an individual's health and safety and on social and occupational roles
substance dependence - More serious pattern of substance use than found in substance abuse; often characterized by drug tolerance
substance - Neurotransmitter involved in sensing pain
successive approximations - Successively reinforcing responses as they more closely resemble the target response
sudden infant death syndrome (SIDS) - Unexpected death of an apparently healthy infant up to age 1 that is not explained by autopsy, medical case information, or an investigation of death scene
superego - In psychodynamic theory, the element of the mind that incorporates parental and societal standards in what is commonly referred to as the conscience as well as the idealistic ego ideal
survey method - Research method that involves collecting information from a selected group of people who are representative of a larger group
symbolic representation - Using a mental thought or activity as a substitute for an actual object
sympathetic division - Subdivision of the autonomic nervous system that is responsible for mobilizing the body in times of stress, preparing for fight or flight
synapse - Site where two or more neurons interact but do not touch
synaptic vesicles - Small pockets or sacs located in the terminal buttons that contain a neurotransmitter
syntax - The organization of words into phrases and sentences
systematic desensitization - A behavioral technique, based on classical conditioning, that is used to treat phobias
tardive dyskinesia - A serious adverse effect of antipsychotic drugs characterized by involuntary motor symptoms such as lip smacking
taste buds - Structures that contain the taste receptors
taste-aversion learning - Development of a dislike or aversion to a flavor or food that has been paired with illness
tectorial membrane - Membrane located above the organ of Corti in the inner ear
teratogen - Any biological, chemical, or physical agent capable of causing birth defects
terminal buttons - Structures located at the ends of the axon in which neurotransmitters are stored before release
thalamus - Subcortical structure that relays incoming sensory information to other parts of the brain
theory - Explanation for a phenomenon based on careful and precise observations
thinking - Manipulation of information in the form of mental images or concepts
tip-of-the-tongue (TOT) phenomenon - Condition of being almost, but not quite, able to remember something; used to investigate the nature of semantic memory
token economy - A technique that reinforces desirable behaviors with tokens (secondary reinforcers), which can be redeemed for other reinforcers, especially primary reinforcers
tolerance - Need for increasing dosages of a drug to achieve the same effect as earlier dosages
trace conditioning - Form of classical conditioning in which the CS comes on and goes off before the US is presented
trait - A summary term that describes the tendency to behave, feel, and think in ways that are consistent across different situations
transduction - Conversion of stimuli received by the receptors into a form (patterns of neural impulses) that can be used by the nervous system
transfer test - An evaluation of the effect of learning one task on the learning of subsequent tasks
transference - In psychoanalysis, the patient's positive or negative reaction to the therapist, which is believed to reflect the patient's relationship to a significant person outside of therapy
trichromatic theory - Theory of color vision stating that there are three types of color receptors
Type A behavior - Collection of behavioral and personality characteristics that include competitiveness, aggressiveness, achievement drive, and inability to relax
ultrasound procedure - Projection of sound waves onto the fetus, uterus, and placenta to construct a sonogram
unconditioned response (UR) - Reaction that is automatically produced when an unconditioned stimulus is presented
unconditioned stimulus (US) - Event that automatically produces an unconditioned response without any previous training
unconscious - Part of the personality that lies outside of awareness yet is believed to be a crucial determinant of behavior
utricle - Fluid-filled chamber in the inner ear that detects changes in gravity
validity - Degree to which a psychological test measures what it purports to measure
vergence eye movements - Movements of the eyes in opposite directions
vestibular sense - System located in the inner ear that allows us to make adjustments to bodily movements and postures
vicarious punishment - Ability to imagine the effects of a punisher
vicarious reinforcement - Ability to imagine the effects of a reinforcer
volemic thirst - Thirst created by a depletion of extracellular fluids
wavelength - Physical length of a light wave measured in nanometers
Weber's law - The observation that the amount of stimulus increase or decrease required to discern a change, divided by the original stimulation, is a constant
withdrawal - Changes in behavior, cognition, and physiology that occur when stopping or reducing the heavy and prolonged use of a substance
working memory - Second stage of short-term memory, where attention and conscious effort are brought to bear on material
Zygote zygote - One-celled organism formed by the union of a sperm and an ovum