Site MapHelpFeedbackGlossary
Glossary
(See related pages)


acceleration programs  Programs for educating the gifted that move them through the curriculum at an unusually rapid pace.
accommodation  Piaget's term for changes in a cognitive structure to include new information.
acquired immune deficiency syndrome (AIDS)  Viral disease that undermines effective functioning of the immune system.
active engagement  Personal involvement in schooling, work, family, or other activity.
active euthanasia  Deliberate action taken to shorten the life of a terminally ill person in order to end suffering or to allow death with dignity; also called mercy killing.
activities of daily living (ADLs)  Essential activities that support survival, such as eating, dressing, bathing, and getting around the house.
activity theory  Theory of aging, proposed by Neugarten and others, that holds that in order to age successfully a person must remain as active as possible.
acute medical conditions  Illnesses that last a short time.
adaptation  Piaget's term for adjustment to new information about the environment, achieved through processes of assimilation and accommodation.
adolescence  Developmental transition between childhood and adulthood entailing major physical, cognitive, and psychosocial changes.
adolescent growth spurt  Sharp increase in height and weight that precedes sexual maturity.
adolescent rebellion  Pattern of emotional turmoil, characteristic of a minority of adolescents, that may involve conflict with family, alienation from adult society, reckless behavior, and rejection of adult values.
advance directive (living will)  Document specifying the type of care wanted by the maker in the event of an incapacitating or terminal illness.
ageism  Prejudice or discrimination against a person (most commonly an older person) based on age.
age-related macular degeneration  Condition in which the center of the retina gradually loses its ability to discern fine details; leading cause of irreversible visual impairment in older adults.
aging in place  Remaining in one's own home, with or without assistance, in later life.
alcoholism  Chronic disease involving dependence on use of alcohol, causing interference with normal functioning and fulfillment of obligations.
alleles  Two or more alternative forms of a gene that occupy the same position on paired chromosomes and affect the same trait.
altruism  Behavior intended to help others out of inner concern and without expectation of external reward; may involve selfdenial or self-sacrifice.
altruistic behavior  Activity intended to help another person with no expectation of reward.
Alzheimer's disease  Progressive, irreversible, degenerative brain disorder characterized by cognitive deterioration and loss of control of bodily functions, leading to death.
ambiguous loss  A loss that is not clearly defined or does not bring closure.
ambivalent (resistant) attachment  Pattern in which an infant becomes anxious before the primary caregiver leaves, is extremely upset during his or her absence, and both seeks and resists contact on his or her return.
amyloid plaque  Waxy chunks of insoluble tissue found in brains of persons with Alzheimer's disease.
animism  Tendency to attribute life to objects that are not alive.
anorexia nervosa  Eating disorder characterized by self-starvation.
anoxia  Lack of oxygen, which may cause brain damage.
anticipatory smiling  Infant smiles at an object and then gazes at an adult while still smiling.
Apgar scale  Standard measurement of a newborn's condition; it assesses appearance, pulse, grimace, activity, and respiration.
art therapy  Therapeutic approach that allows a person to express troubled feelings without words, using a variety of art materials and media.
assimilation  Piaget's term for incorporation of new information into an existing cognitive structure.
assisted suicide  Suicide in which a physician or someone else helps a person take his or her own life.
asthma  A chronic respiratory disease characterized by sudden attacks of coughing, wheezing, and difficulty in breathing.
attachment  Reciprocal, enduring tie between two people—especially between infant and caregiver—each of whom contributes to the quality of the relationship.
attention-deficit/hyperactivity disorder (ADHD)  Syndrome characterized by persistent inattention and distractibility, impulsivity, low tolerance for frustration, and inappropriate overactivity.
authoritarian parenting  In Baumrind's terminology, parenting style emphasizing control and obedience.
authoritative parenting  In Baumrind's terminology, parenting style blending respect for a child's individuality with an effort to instill social values.
autobiographical memory  Memory of specific events in one's life.
autoimmunity  Tendency of an aging body to mistake its own tissues for foreign invaders and to attack and destroy them.
autonomy versus shame and doubt  Erikson's second stage in psychosocial development, in which children achieve a balance between selfdetermination and control by others.
autosomes  In humans, the 22 pairs of chromosomes not related to sexual expression.
avoidant attachment  Pattern in which an infant rarely cries when separated from the primary caregiver and avoids contact on his or her return.
balanced investment  Pattern of retirement activity allocated among family, work, and leisure.
basal metabolism  Use of energy to maintain vital functions.
basic trust versus basic mistrust  Erikson's first stage in psychosocial development, in which infants develop a sense of the reliability of people and objects.
Bayley Scales of Infant and Toddler Development  Standardized test of infants' and toddlers' mental and motor development.
behavioral genetics  Quantitative study of relative hereditary and environmental influences on behavior.
behaviorism  Learning theory that emphasizes the predict-able role of environment in causing observable behavior.
behaviorist approach  Approach to the study of cognitive development that is concerned with basic mechanics of learning.
behavior therapy  Therapeutic approach using principles of learning theory to encourage desired behaviors or eliminate undesired ones; also called behavior modification.
bereavement  Loss, due to death, of someone to whom one feels close and the process of adjustment to the loss.
bilingual  Fluent in two languages.
bilingual education  System of teaching non-English-speaking children in their native language while they learn English, and later switching to all-English instruction.
bioecological theory  Bronfenbrenner's approach to understanding processes and contexts of human development that identifies five levels of environmental influence.
body image  Descriptive and evaluative beliefs about one's appearance.
Brazelton Neonatal Behavioral Assessment Scale (NBAS)  Neurological and behavioral test to measure neonate's responses to the environment.
bulimia nervosa  Eating disorder in which a person regularly eats huge quantities of food and then purges the body by laxatives, induced vomiting, fasting, or excessive exercise.
bullying  Aggression deliberately and persistently directed against a particular target, or victim, typically one who is weak, vulnerable, and defenseless.
canalization  Limitation on variance of expression of certain inherited characteristics.
caregiver burnout  Condition of physical, mental, and emotional exhaustion affecting adults who provide continuous care for sick or aged persons.
case study  Study of a single subject, such as an individual or family.
cataracts  Cloudy or opaque areas in the lens of the eye, which cause blurred vision.
cell death  In brain development, normal elimination of excess brain cells to achieve more efficient functioning.
central executive  In Baddeley's model, element of working memory that controls the processing of information.
central nervous system  Brain and spinal cord.
centration  In Piaget's theory, the tendency of preoperational children to focus on one aspect of a situation and neglect others.
cephalocaudal principle  Principle that development proceeds in a head-to-tail direction, that is, that upper parts of the body develop before lower parts of the trunk.
cesarean delivery  Delivery of a baby by surgical removal from the uterus.
child-directed speech (CDS)  Form of speech often used in talking to babies or toddlers; includes slow, simplified speech, a high-pitched tone, exaggerated vowel sounds, short words and sentences, and much repetition; also called parentese or motherese.
childhood depression  Mood disorder characterized by such symptoms as a prolonged sense of friendlessness, inability to have fun or concentrate, fatigue, extreme activity or apathy, feelings of worthlessness, weight change, physical complaints, and thoughts of death or suicide.
chromosomes  Coils of DNA that consist genes.
chronic medical conditions  Illnesses or impairments that persist for at least 3 months.
circular reactions  Piaget's term for processes by which an infant learns to reproduce desired occurrences originally discovered by chance.
classical conditioning  Learning based on associating a stimulus that does not ordinarily elicit a response with another stimulus that does elicit the response.
class inclusion  Understanding of the relationship between a whole and its parts.
code mixing  Use of elements of two languages, sometimes in the same utterance, by young children in households where both languages are spoken.
code switching  Changing one's speech to match the situation, as in people who are bilingual.
cognitive-appraisal model  Model of coping, proposed by Lazarus and Folkman, that holds that, on the basis of continuous appraisal of their relationship with the environment, people choose appropriate coping strategies to deal with situations that tax their normal resources.
cognitive development  Pattern of change in mental abilities, such as learning, attention, memory, language, thinking, reasoning, and creativity.
cognitive neuroscience  Study of links between neural processes and cognitive abilities.
cognitive neuroscience approach  Approach to the study of cognitive development that links brain processes with cognitive ones.
cognitive perspective  View that thought processes are central to development.
cognitive reserve  Hypothesized fund of energy that may enable a deteriorating brain to continue to function normally.
cognitive-stage theory  Piaget's theory that children's cognitive development advances in a series of four stages involving qualitatively distinct types of mental operations.
cohort  A group of people born at about the same time.
commitment  Marcia's term for personal investment in an occupation or system of beliefs.
committed compliance  Kochanska's term for wholehearted obedience of a parent's orders without reminders or lapses.
componential element  Sternberg's term for the analytic aspect of intelligence.
conceptual knowledge  Acquired interpretive understandings stored in long-term memory.
concordant  Term describing tendency of twins to share the same trait or disorder.
concrete operations  Third stage of Piagetian cognitive development (approximately ages 7 to 12), during which children develop logical but not abstract thinking.
conduct disorder (CD)  Repetitive, persistent pattern of aggressive, antisocial behavior violating societal norms or the rights of others.
conscience  Internal standards of behavior, which usually control one's conduct and produce emotional discomfort when violated.
conservation  Piaget's term for awareness that two objects that are equal according to a certain measure remain equal in the face of perceptual alteration so long as nothing has been added to or taken away from either object.
constructive play  Play involving use of objects or materials to make something.
contextual element  Sternberg's term for the practical aspect of intelligence.
contextual perspective  View of human development that sees the individual as inseparable from the social context.
continuity theory  Theory of aging, described by Atchley, that holds that in order to age successfully people must maintain a balance of continuity and change in both the internal and external structures of their lives.
control group  In an experiment, a group of people, similar to those in the experimental group, who do not receive the treatment under study.
conventional morality (or morality of conventional role conformity)  Second level in Kohlberg's theory of moral reasoning in which standards of authority figures are internalized.
convergent thinking  Thinking aimed at finding the one right answer to a problem.
coping  Adaptive thinking or behavior aimed at reducing or relieving stress that arises from harmful, threatening, or challenging conditions.
coregulation  Transitional stage in the control of behavior in which parents exercise general supervision and children exercise moment-to-moment self-regulation.
corporal punishment  Use of physical force with the intention of causing pain but not injury so as to correct or control behavior.
correlational study  Research design intended to discover whether a statistical relationship between variables exists.
creativity  Ability to see situations in a new way, to produce innovations, or to discern previously unidentified problems and find novel solutions.
crisis  Marcia's term for period of conscious decision making related to identity formation.
critical period  Specific time when a given event or its absence has a specific impact on development.
cross-modal transfer  Ability to use information gained by one sense to guide another.
cross-sectional study  Study designed to assess age-related differences, in which people of different ages are assessed on one occasion.
crystallized intelligence  Type of intelligence, proposed by Horn and Cattell, involving the ability to remember and use learned information; it is largely dependent on education and culture.
cultural bias  Tendency of intelligence tests to include items calling for knowledge or skills more familiar or meaningful to some cultural groups than to others.
cultural socialization  Parental practices that teach children about their racial/ethnic heritage and promote cultural practices and cultural pride.
culture  A society's or group's total way of life, including customs, traditions, beliefs, values, language, and physical products—all learned behavior, passed on from parents to children.
culture-fair tests  Intelligence tests that deal with experiences common to various cultures, in an attempt to avoid cultural bias.
culture-free tests  Intelligence tests that, if they were possible to design, would have no culturally linked content.
culture-relevant tests  Intelligence tests that would draw on and adjust for culturally related content.
decenter  In Piaget's terminology, to think simultaneously about several aspects of a situation.
declarative knowledge  Acquired factual knowledge stored in long-term memory.
decoding  Process of phonetic analysis by which a printed word is converted to spoken form before retrieval from long-term memory.
deductive reasoning  Type of logical reasoning that moves from a general premise about a class to a conclusion about a particular member or members of the class.
deferred imitation  Piaget's term for reproduction of an observed behavior after the passage of time by calling up a stored symbol of it.
dementia  Deterioration in cognitive and behavioral functioning due to physiological causes.
Denver Developmental Screening Test  Screening test given to children 1 month to 6 years old to determine whether they are developing normally.
deoxyribonucleic acid (DNA)  Chemical that carries inherited instructions for the development of all cellular forms of life.
dependent variable  In an experiment, the condition that may or may not change as a result of changes in the independent variable.
depth perception  Ability to perceive objects and surfaces three-dimensionally.
developmental tasks  In normative-stage theories, typical challenges that need to be mastered for successful adaptation to each stage of life.
developmental tests  Psychometric tests that compare a baby's performance on a series of tasks with standardized norms for particular ages.
diabetes  (1) One of the most common diseases of childhood. It is characterized by high levels of glucose in the blood as a result of defective insulin production, ineffective insulin action, or both. (2) Disease in which the body does not produce or properly use insulin, a hormone that converts sugar, starches, and other foods into energy needed for daily life.
differentiation  Process by which cells acquire specialized structures and functions.
"difficult" children  Children with irritable temperament, irregular biological rhythms, and intense emotional responses.
discipline  Methods of molding children's character and of teaching them to exercise self-control and engage in acceptable behavior.
disengagement theory  Theory of aging, proposed by Cumming and Henry, that holds that successful aging is characterized by mutual withdrawal of the older person and society.
dishabituation  Increase in responsiveness after presentation of a new stimulus.
disorganized-disoriented attachment  Pattern in which an infant, after separation from the primary caregiver, shows contradictory repetitious, or misdirected behaviors on his or her return.
divergent thinking  Thinking that produces a variety of fresh, diverse possibilities.
dizygotic twins  Twins conceived by the union of two different ova (or a single ovum that has split) with two different sperm cells; also called fraternal twins; they are no more alike genetically than any other siblings.
dominant inheritance  Pattern of inheritance in which, when a child receives different alleles, only the dominant one is expressed.
Down syndrome  Chromosomal disorder characterized by moderate-to-severe mental retardation and by such physical signs as a downward-sloping skin fold at the inner corners of the eyes. Also called trisomy-21.
dramatic play  Play involving imaginary people or situations; also called pretend play, fantasy play, or imaginative play.
drug therapy  Administration of drugs to treat emotional disorders.
dual representation hypothesis  Proposal that children under age 3 have difficulty grasping spatial relationships because of the need to keep more than one mental representation in mind at the same time.
durable power of attorney  Legal instrument that appoints an individual to make decisions in the event of another person's incapacitation.
dynamic systems theory (DST)  Esther Thelen's theory, which holds that motor development is a dynamic process of active coordination of multiple systems within the infant in relation to the environment.
dynamic tests  Tests based on Vygotsky's theory that emphasize potential rather than past learning.
dyslexia  Developmental disorder in which reading achievement is substantially lower than predicted by IQ or age.
early intervention  Systematic process of providing services to help families meet young children's developmental needs.
"easy" children  Children with a generally happy temperament, regular biological rhythms, and a readiness to accept new experiences.
ecological theory of perception  Theory developed by Eleanor and James Gibson, which describes developing motor and perceptual abilities as interdependent parts of a functional system that guides behavior in varying contexts.
egocentrism  Piaget's term for inability to consider another person's point of view; a characteristic of young children's thought.
ego-control  Self-control and the selfregulation of impulses.
ego integrity versus despair  According to Erikson, the eighth and final stage of psychosocial development, in which people in late adulthood either achieve a sense of integrity of the self by accepting the lives they have lived, and thus accept death, or yield to despair that their lives cannot be relived.
ego-resiliency  (1) Dynamic capacity to modify one's level of ego-control in response to environmental and contextual influences. (2) The ability to adapt flexibly and resourcefully to potential sources of stress.
elaboration  Mnemonic strategy of making mental associations involving items to be remembered.
electronic fetal monitoring  Mechanical monitoring of fetal heartbeat during labor and delivery.
elicited imitation  Research method in which infants or toddlers are induced to imitate a specific series of actions they have seen but not necessarily done before.
embryonic stage  Second stage of gestation (2 to 8 weeks), characterized by rapid growth and development of major body systems and organs.
emergent literacy  Preschoolers' development of skills, knowledge, and attitudes that underlie reading and writing.
emerging adulthood  Proposed transitional period between adolescence and adulthood commonly found in industrialized countries.
emotional intelligence (EI)  Salovey and Mayer's term for the ability to understand and regulate emotions; an important component of effective, intelligent behavior.
emotional maltreatment  Rejection, terrorization, isolation, exploitation, degradation, ridicule, or failure to provide emotional support, love, and affection; or other action or inaction that may cause behavioral, cognitive, emotional, or mental disorders.
emotion-focused coping  In the cognitive appraisal model, coping strategy directed toward managing the emotional response to a stressful situation so as to lessen its physical or psychological impact.
emotions  Subjective reactions to experience that are associated with physiological and behavioral changes.
empathy  Ability to put oneself in another person's place and feel what the other person feels.
empty nest  Transitional phase of parenting following the last child's leaving the parents' home.
encapsulation  In Hoyer's terminology, progressive dedication of information processing and fluid thinking to specific knowledge systems, making knowledge more readily accessible.
encoding  Process by which information is prepared for long-term storage and later retrieval.
English-immersion approach  Approach to teaching English as a second language in which instruction is presented only in English.
enrichment programs  Programs for educating the gifted that broaden and deepen knowledge and skills through extra activities, projects, field trips, or mentoring.
enuresis  Repeated urination in clothing or in bed.
environment  Totality of nonhereditary, or experiential, influences on development.
epigenesis  Mechanism that turns genes on or off and determines functions of body cells.
episodic memory  Long-term memory of specific experiences or events, linked to time and place.
equilibration  Piaget's term for the tendency to seek a stable balance among cognitive elements; achieved through a balance between assimilation and accommodation.
erectile dysfunction  Inability of a man to achieve or maintain an erect penis sufficient for satisfactory sexual performance.
ethnic gloss  Overgeneralization about an ethnic or cultural group that obscures differences within the group.
ethnic group  A group united by ancestry, race, religion, language, or national origins, which contribute to a sense of shared identity.
ethnographic study  In-depth study of a culture, which uses a combination of methods including participant observation.
ethology  Study of distinctive adaptive behaviors of species of animals that have evolved to increase survival of the species.
evolutionary psychology  Application of Darwinian principles of natural selection and survival of the fittest to individual behavior.
evolutionary/sociobiological perspective  View of human development that focuses on evolutionary and biological bases of behavior.
executive function  Conscious control of thoughts, emotions, and actions to accomplish goals or solve problems.
executive functioning  A set of mental processes that control and regulate other behaviors.
experiential element  Sternberg's term for the insightful or creative aspect of intelligence.
experiment  Rigorously controlled, replicable procedure in which the researcher manipulates variables to assess the effect of one on the other.
experimental group  In an experiment, the group receiving the treatment under study.
explicit memory  Intentional and conscious memory, generally of facts, names, and events.
extended family  Multigenerational kinship network of parents, children, and other relatives, sometimes living together in an extended-family household.
externalizing behaviors  Behaviors by which a child acts out emotional difficulties; for example, aggression or hostility.
external memory aids  Mnemonic strategies using something outside the person.
family-focused lifestyle  Pattern of retirement activity that revolves around family, home, and companions.
family therapy  Psychological treatment in which a therapist sees the whole family together to analyze patterns of family functioning.
fast mapping  Process by which a child absorbs the meaning of a new word after hearing it once or twice in conversation.
fertilization  Union of sperm and ovum to produce a zygote; also called conception.
fetal alcohol syndrome (FAS)  Combination of mental, motor, and developmental abnormalities affecting the off spring of some women who drink heavily during pregnancy.
fetal stage  Final stage of gestation (from 8 weeks to birth), characterized by increased differentiation of body parts and greatly enlarged body size.
fictive kin  Friends who are considered and behave like family members.
filial crisis  In Marcoen's terminology, normative development of middle age, in which adults learn to balance love and duty to their parents with autonomy within a two-way relationship.
filial maturity  Stage of life, proposed by Marcoen and others, in which middle-aged children, as the outcome of a filial crisis, learn to accept and meet their parents' need to depend on them.
fine motor skills  Physical skills that involve the small muscles and eye-hand coordination.
five-factor model  Theoretical model of personality, developed and tested by Costa and McCrae, based on the "Big Five" factors underlying clusters of related personality traits: neuroticism, extraversion, openness to experience, conscientiousness, and agreeableness.
fluid intelligence  Type of intelligence, proposed by Horn and Cattell, that is applied to novel problems and is relatively independent of educational and cultural influences.
foreclosure  Identity status, described by Marcia, in which a person who has not spent time considering alternatives (that is, has not been in crisis) is committed to other people's plans for his or her life.
formal games with rules  Organized games with known procedures and penalties.
formal operations  Piaget's final stage of cognitive development, characterized by the ability to think abstractly.
free radicals  Unstable, highly reactive atoms or molecules, formed during metabolism, which can cause internal bodily damage.
functional age  Measure of a person's ability to function effectively in his or her physical and social environment in comparison with others of the same chronological age.
functional play  Play involving repetitive large muscular movements.
gender  Significance of being male or female.
gender constancy  Awareness that one will always be male or female; also called sexcategory constancy.
gender crossover  Gutmann's term for reversal of gender roles after the end of active parenting.
gender identity  Awareness, developed in early childhood, that one is male or female.
gender roles  Behaviors, interests, attitudes, skills, and traits that a culture considers appropriate for each sex; differ for males and females.
gender-schema theory  Theory, proposed by Bem, that children socialize themselves in their gender roles by developing a mentally organized network of information about what it means to be male or female in a particular culture.
gender segregation  Tendency to select playmates of one's own gender.
gender stereotypes  Preconceived generalizations about male or female role behavior.
gender-typing  Socialization process by which children, at an early age, learn appropriate gender roles.
generalized anxiety disorder  Anxiety not focused on any single target.
generativity  Erikson's term for concern of mature adults for establishing, guiding, and influencing the next generation.
generativity versus stagnation  Erikson's seventh stage of psychosocial development, in which the middle-aged adult develops a concern with establishing, guiding, and influencing the next generation or else experiences stagnation (a sense of inactivity or lifelessness).
generic memory  Memory that produces scripts of familiar routines to guide behavior.
genes  Small segments of DNA located in definite positions on particular chromosomes; functional units of heredity.
genetic code  Sequence of bases within the DNA molecule; governs the formation of proteins that determine the structure and functions of living cells.
genetic counseling  Clinical service that advises prospective parents of their probable risk of having children with hereditary defects.
genetic-programming theories  Theories that explain biological aging as resulting from a genetically determined developmental timetable.
genotype  Genetic makeup of a person, containing both expressed and unexpressed characteristics.
genotype-environment correlation  Tendency of certain genetic and environmental influences to reinforce each other; may be passive, reactive (evocative), or active. Also called genotype-environment covariance.
genotype-environment interaction  The portion of phenotypic variation that results from the reactions of genetically different individuals to similar environmental conditions.
geriatrics  Branch of medicine concerned with processes of aging and medical conditions associated with old age.
germinal stage  First 2 weeks of prenatal development, characterized by rapid cell division, blastocyst formation, and implantation in the wall of the uterus.
gerontology  Study of the aged and the process of aging.
gestation  Period of development between conception and birth.
gestational age  Age of an unborn baby, usually dated from the first day of an expectant mother's last menstrual cycle.
glaucoma  Irreversible damage to the optic nerve caused by increased pressure in the eye.
goodness of fit  Appropriateness of environmental demands and constraints to a child's temperament.
grief  Emotional response experienced in the early phases of bereavement.
grief work  Working out of psychological issues connected with grief.
gross motor skills  Physical skills that involve the large muscles.
guided participation  Adult's participation in a child's activity that helps to structure it and bring the child's understanding of it closer to the adult's.
habituation  Type of learning in which familiarity with a stimulus reduces, slows, or stops a response.
handedness  Preference for using a particular hand.
haptic perception  Ability to acquire information about properties of objects, such as size, weight, and texture, by handling them.
Hayflick limit  Genetically controlled limit, proposed by Hayflick, on the number of times cells can divide in members of a species.
heredity  Inborn traits or characteristics inherited from the biological parents.
heritability  Statistical estimate of contribution of heredity to individual differences in a specific trait within a given population.
heterozygous  Possessing differing alleles for a trait.
historical generation  A group of people strongly influenced by a major historical event during their formative period.
holophrase  Single word that conveys a complete thought.
Home Observation for Measurement of the Environment (HOME)  Instrument to measure the influence of the home environment on children's cognitive growth.
homozygous  Possessing two identical alleles for a trait.
hormone therapy (HT)  Treatment with artificial estrogen, sometimes in combination with the hormone progesterone, to relieve or prevent symptoms caused by decline in estrogen levels after menopause.
hospice care  Warm, personal, patient and family-centered care for a person with a terminal illness.
hostile attribution bias  Tendency to perceive others as trying to hurt one and to strike out in retaliation or self-defense.
human development  Scientific study of processes of change and stability throughout the human life span.
human genome  Complete sequence of genes in the human body.
hypertension  Chronically high blood pressure.
hypotheses  Possible explanations for phenomena, used to predict the outcome of research.
hypothetical-deductive reasoning  Ability, believed by Piaget, to accompany the stage of formal operations, to develop, consider, and test hypotheses.
ideal self  The self one would like to be.
identification  In Freudian theory, the process by which a young child adopts characteristics, beliefs, attitudes, values, and behaviors of the parent of the same sex.
identity  According to Erikson, a coherent conception of the self, made up of goals, values, and beliefs to which a person is solidly committed.
identity accommodation  Whitbourne's term for adjusting the self-concept to fit new experience.
identity achievement  Identity status, described by Marcia, that is characterized by commitment to choices made following a crisis, a period spent in exploring alternatives.
identity assimilation  Whitbourne's term for effort to fit new experience into an existing self-concept.
identity balance  Whitbourne's term for a tendency to balance assimilation and accommodation.
identity diffusion  Identity status, described by Marcia, that is characterized by absence of commitment and lack of serious consideration of alternatives.
identity process theory (IPT)  Whitbourne's theory of identity development based on processes of assimilation and accommodation.
identity schemas  Accumulated perceptions of the self shaped by incoming information from intimate relationships, work-related situations, and community and other experiences.
identity statuses  Marcia's term for states of ego development that depend on the presence or absence of crisis and commitment.
identity versus identity confusion  Erikson's fifth stage of psychosocial development, in which an adolescent seeks to develop a coherent sense of self, including the role she or he is to play in society. Also called identity versus role confusion.
implicit memory  Unconscious recall, generally of habits and skills; sometimes called procedural memory.
imprinting  Instinctive form of learning in which, during a critical period in early development, a young animal forms an attachment to the first moving object it sees, usually the mother.
incomplete dominance  Pattern of inheritance in which a child receives two different alleles, resulting in partial expression of a trait.
independent variable  In an experiment, the condition over which the experimenter has direct control.
individual differences  Differences in characteristics, influences, or developmental outcomes.
individual psychotherapy  Psychological treatment in which a therapist sees a troubled person one-on-one.
individuation  (1) Adolescents' struggle for autonomy and personal identity. (2) Jung's term for emergence of the true self through balancing or integration of conflicting parts of the personality.
inductive reasoning  Type of logical reasoning that moves from particular observations about members of a class to a general conclusion about that class.
inductive techniques  Disciplinary techniques designed to induce desirable behavior by appealing to a child's sense of reason and fairness.
industry versus inferiority  Erikson's fourth stage of psychosocial development, in which children must learn the productive skills their culture requires or else face feelings of inferiority.
infant mortality rate  Proportion of babies born alive who die within the 1st year.
infertility  Inability to conceive a child after 12 months of sexual intercourse without the use of birth control.
information-processing approach  (1) Approach to the study of cognitive development by observing and analyzing the mental processes involved in perceiving and handling information. (2) Approach to the study of cognitive development that analyzes processes involved in perceiving and handling information.
initiative versus guilt  Erikson's third stage in psychosocial development, in which children balance the urge to pursue goals with reservations about doing so.
instrumental aggression  Aggressive behavior used as a means of achieving a goal.
integration  Process by which neurons coordinate the activities of muscle groups.
intellectual disability  Significantly subnormal cognitive functioning. Also referred to as cognitive disability or mental retardation.
intelligent behavior  Behavior that is goal oriented and adaptive to circumstances and conditions of life.
interiority  Neugarten's term for a concern with inner life (introversion or introspection), which usually appears in middle age.
internalization  During socialization, process by which children accept societal standards of conduct as their own.
internalizing behaviors  Behaviors by which emotional problems are turned inward; for example, anxiety or depression.
intimacy versus isolation  Erikson's sixth stage of psychosocial development, in which young adults either form strong, long-lasting bonds with friends and romantic partners or face a possible sense of isolation and selfabsorption.
invisible imitation  Imitation with parts of one's body that one cannot see.
IQ (intelligence quotient) tests  Psychometric tests that seek to measure intelligence by comparing a test-taker's performance with standardized norms.
irreversibility  Piaget's term for a preoperational child's failure to understand that an operation can go in two or more directions.
kangaroo care  Method of skin-to-skin contact in which a newborn is laid face down between the mother's breasts for an hour or so at a time after birth.
Kaufman Assessment Battery for Children (K-ABC-II)  Nontraditional individual intelligence test designed to provide fair assessments of minority children and children with disabilities.
kinship care  Care of children living without parents in the home of grandparents or other relatives, with or without a change of legal custody.
laboratory observation  Research method in which all participants are observed under the same controlled conditions.
language  Communication system based on words and grammar.
language acquisition device (LAD)  In Chomsky's terminology, an inborn mechanism that enables children to infer linguistic rules from the language they hear.
lateralization  Tendency of each of the brain's hemispheres to have specialized functions.
learning disabilities (LDs)  Disorders that interfere with specific aspects of learning and school achievement.
learning perspective  View of human development that holds that changes in behavior result from experience or from adaptation to the environment.
life expectancy  Age to which a person in a particular cohort is statistically likely to live (given his or her current age and health status), on the basis of average longevity of a population.
life review  Reminiscence about one's life in order to see its significance.
life span  The longest period that members of a species can live.
life-span development  Concept of human development as a lifelong process, which can be studied scientifically.
life structure  In Levinson's theory, the underlying pattern of a person's life at a given time, built on whatever aspects of life the person finds most important.
linguistic speech  Verbal expression designed to convey meaning.
literacy  (1) Ability to read and write. (2) In an adult, ability to use printed and written information to function in society, achieve goals, and develop knowledge and potential.
longevity  Length of an individual's life.
longitudinal study  Study designed to assess age changes in a sample over time.
long-term memory  Storage of virtually unlimited capacity that holds information for long periods.
low birth weight  Weight of less than 5½ pounds (2,500 grams) at birth because of prematurity or being small-for-date.
mammography  Diagnostic X-ray examination of the breasts.
marital capital  Financial and emotional benefits built up during a long-standing marriage, which tend to hold a couple together.
maturation  Unfolding of a natural sequence of physical and behavioral changes.
mechanistic model  Model that views human development as a series of predictable responses to stimuli.
menarche  Girl's first menstruation.
menopause  Cessation of menstruation and of ability to bear children.
metabolism  Conversion of food and oxygen into energy.
metacognition  Awareness of a person's own mental processes.
metamemory  Understanding of processes of memory.
midlife crisis  In some normative-crisis models, stressful life period precipitated by the review and reevaluation of one's past, typically occurring in the early to middle forties.
midlife review  Introspective examination that often occurs in middle age, leading to reappraisal and revision of values and priorities.
mirror neurons  Neurons that fire when a person does something or observes someone else doing the same thing.
mnemonic strategies  Techniques to aid memory.
monozygotic twins  Twins resulting from the division of a single zygote after fertilization; also called identical twins; they are genetically similar.
moratorium  Identity status, described by Marcia, in which a person is currently considering alternatives (in crisis) and seems headed for commitment.
multifactorial transmission  Combination of genetic and environmental factors to produce certain complex traits.
mutations  Permanent alterations in genes or chromosomes that may produce harmful characteristics.
mutual regulation  Process by which infant and caregiver communicate emotional states to each other and respond appropriately.
myelination  Process of coating neural pathways with a fatty substance called myelin, which enables faster communication between cells.
myopia  Nearsightedness.
nativism  Theory that human beings have an inborn capacity for language acquisition.
natural childbirth  Method of childbirth that seeks to prevent pain by eliminating the mother's fear through education about the physiology of reproduction and training in breathing and relaxation during delivery.
naturalistic observation  Research method in which behavior is studied in natural settings without intervention or manipulation.
neglect  Failure to meet a dependent's basic needs.
neonatal jaundice  Condition, in many newborn babies, caused by immaturity of liver and evidenced by yellowish appearance; can cause brain damage if not treated promptly.
neonatal period  First 4 weeks of life, a time of transition from intrauterine dependency to independent existence.
neonate  Newborn baby, up to 4 weeks old.
neurofibrillary tangles  Twisted masses of protein fibers found in brains of persons with Alzheimer's disease.
neurons  Nerve cells.
niche-picking  Tendency of a person, especially after early childhood, to seek out environments compatible with his or her genotype.
nonnormative  Characteristic of an unusual event that happens to a particular person or a typical event that happens at an unusual time of life.
nonorganic failure to thrive  Slowed or arrested physical growth with no known medical cause, accompanied by poor developmental and emotional functioning.
nonshared environmental effects  The unique environment in which each child grows up, consisting of distinctive influences or influences that affect one child differently than another.
normative  Characteristic of an event that occurs in a similar way for most people in a group.
normative life events  In the timing-of-events model, commonly expected life experiences that occur at customary times.
normative-stage models  Theoretical models that describe psychosocial development in terms of a definite sequence of age-related changes.
nuclear family  Two-generational kinship, economic, and household unit consisting of one or two parents and their biological children, adopted children, or stepchildren.
obesity  Extreme overweight in relation to age, sex, height, and body type as defined by having a body mass index at or above the 95th percentile.
object permanence  Piaget's term for the understanding that a person or object still exists when out of sight.
observational learning  Learning through watching the behavior of others.
obsessive-compulsive disorder (OCD)  Anxiety aroused by repetitive, intrusive thoughts, images, or impulses, often leading to compulsive ritual behaviors.
operant conditioning  (1) Learning based on association of behavior with its consequences. (2) Learning based on reinforcement or punishment.
operational definition  Definition stated solely in terms of the operations or procedures used to produce or measure a phenomenon.
oppositional defiant disorder (ODD)  Pattern of behavior, persisting into middle childhood, marked by negativity, hostility, and defiance.
organismic model  Model that views human development as internally initiated by an active organism and as occurring in a sequence of qualitatively different stages.
organization  (1) Piaget's term for the creation of categories or systems of knowledge. (2) Mnemonic strategy of categorizing material to be remembered.
osteoporosis  Condition in which the bones become thin and brittle as a result of rapid calcium depletion.
Otis-Lennon School Ability Test (OLSAT 8)  Group intelligence test for kindergarten through 12th grade.
overt (direct) aggression  Aggression that is openly directed at its target.
palliative care  Care aimed at relieving pain and suffering and allowing the terminally ill to die in peace, comfort, and dignity. Also called comfort care.
Parkinson's disease  Progressive, irreversible degenerative neurological disorder, characterized by tremor, stiffness, slowed movement, and unstable posture.
participant observation  Research method in which the observer lives with the people or participates in the activity being observed.
parturition  Process of uterine, cervical, and other changes, usually lasting about 2 weeks, preceding childbirth.
passive euthanasia  Deliberate withholding or discontinuation of life-prolonging treatment of a terminally ill person in order to end suffering or allow death with dignity.
perimenopause  Period of several years during which a woman experiences physiological changes of menopause; includes first year after end of menstruation; also called climacteric.
permissive parenting  In Baumrind's terminology, parenting style emphasizing self-expression and self-regulation.
personality  The relatively consistent blend of emotions, temperament, thought, and behavior that makes a person unique.
phenotype  Observable characteristics of a person.
phonetic (code-emphasis) approach  Approach to teaching reading that emphasizes decoding of unfamiliar words.
physical abuse  Action taken deliberately to endanger another person, involving potential bodily injury.
physical development  Growth of body and brain, including patterns of change in sensory capacities, motor skills, and health.
Piagetian approach  Approach to the study of cognitive development that describes qualitative stages in cognitive functioning.
plasticity  (1) Range of modifiability of performance. (2) Modifiability, or "molding," of the brain through experience.
play therapy  Therapeutic approach that uses play to help a child cope with emotional distress.
polygenic inheritance  Pattern of inheritance in which multiple genes at different sites on chromosomes affect a complex trait.
postconventional morality (or morality of autonomous moral principles)  Third level of Kohlberg's theory of moral reasoning, in which people follow internally held moral principles and can decide among conflicting moral standards.
postformal thought  Mature type of thinking that relies on subjective experience and intuition as well as logic and allows room for ambiguity, uncertainty, inconsistency, contradiction, imperfection, and compromise.
postmature  A fetus not yet born as of 2 weeks after the due date or 42 weeks after the mother's last menstrual period.
power assertion  Disciplinary strategy designed to discourage undesirable behavior through physical or verbal enforcement of parental control.
pragmatics  (1) The practical knowledge needed to use language for communicative purposes. (2) Set of linguistic rules that govern the use of language for communication.
preconventional morality  First level of Kohlberg's theory of moral reasoning in which control is external and rules are obeyed in order to gain rewards or avoid punishment or out of self-interest.
prejudice  Unfavorable attitude toward members of certain groups outside one's own, especially racial or ethnic groups.
prelinguistic speech  Forerunner of linguistic speech; utterance of sounds that are not words. Includes crying, cooing, babbling, and accidental and deliberate imitation of sounds without understanding their meaning.
premenstrual syndrome (PMS)  Disorder producing symptoms of physical discomfort and emotional tension for up to 2 weeks before a menstrual period.
preoperational stage  In Piaget's theory, the second major stage of cognitive development, in which symbolic thought expands but children cannot yet use logic.
prepared childbirth  Method of childbirth that uses instruction, breathing exercises, and social support to induce controlled physical responses to uterine contractions and reduce fear and pain.
presbycusis  Age-related, gradual loss of hearing, which accelerates after age 55, especially with regard to sounds at higher frequencies.
presbyopia  Age-related, progressive loss of the eyes' ability to focus on nearby objects due to loss of elasticity in the lens.
pretend play  Play involving imaginary people and situations; also called fantasy play, dramatic play, or imaginative play.
preterm (premature) infants  Infants born before completing the 37th week of gestation.
primary aging  Gradual, inevitable process of bodily deterioration throughout the life span.
primary sex characteristics  Organs directly related to reproduction, which enlarge and mature during adolescence.
private speech  Talking aloud to oneself with no intent to communicate with others.
problem-focused coping  In the cognitive appraisal model, coping strategy directed toward eliminating, managing, or improving a stressful situation.
procedural knowledge  Acquired skills stored in long-term memory.
procedural memory  Long-term memory of motor skills, habits, and ways of doing things, which can be recalled without conscious effort; sometimes called implicit memory.
prosocial behavior  Any voluntary behavior intended to help others.
protective factors  (1) Influences that reduce the impact of potentially negative influences and tend to predict positive outcomes. (2) Influences that reduce the impact of early stress and tend to predict positive outcomes.
proximodistal principle  Principle that development proceeds from within to without, that is, that parts of the body near the center develop before the extremities.
psychoanalytic perspective  View of human development as shaped by unconscious forces that motivate human behavior.
psychometric approach  Approach to the study of cognitive development that seeks to measure intelligence quantitatively.
psychosexual development  In Freudian theory, an unvarying sequence of stages of childhood personality development in which gratification shifts from the mouth to the anus and then to the genitals.
psychosocial development  (1) Pattern of change in emotions, personality, and social relationships. (6) (2) In Erikson's eight-stage theory, the socially and culturally influenced process of development of the ego, or self.
puberty  Process by which a person attains sexual maturity and the ability to reproduce.
punishment  The process by which a behavior is weakened, decreasing the likelihood of repetition.
qualitative change  Discontinuous changes in kind, structure, or organization.
qualitative research  Research that focuses on nonnumerical data, such as subjective experiences, feelings, or beliefs.
quantitative change  Changes in number or amount, such as in height, weight, size of vocabulary, or frequency of communication.
quantitative research  Research that deals with objectively measurable data.
random assignment  Assignment of participants in an experiment to groups in such a way that each person has an equal chance of being placed in any group.
random selection  Selection of a sample in such a way that each person in a population has an equal and independent chance of being chosen.
reaction range  Potential variability, depending on environmental conditions, in the expression of a hereditary trait.
real self  The self one actually is.
recall  Ability to reproduce material from memory.
recentering  Process that underlies the shift to an adult identity.
receptive cooperation  Kochanska's term for eager willingness to cooperate harmoniously with a parent in daily interactions, including routines, chores, hygiene, and play.
recessive inheritance  Pattern of inheritance in which a child receives identical recessive alleles, resulting in expression of a nondominant trait.
reciprocal determinism  Bandura's term for bidirectional forces that affect development.
recognition  Ability to identify a previously encountered stimulus.
reflective thinking  Type of logical thinking that becomes more prominent in adulthood, involving continuous, active evaluation of information and beliefs in the light of evidence and implications.
reflex behaviors  Automatic, involuntary, innate responses to stimulation.
rehearsal  Mnemonic strategy to keep an item in working memory through conscious repetition.
reinforcement  The process by which a behavior is strengthened, increasing the likelihood that the behavior will be repeated.
relational (social or indirect) aggression  Aggression aimed at damaging or interfering with another person's relationships, reputation, or psychological wellbeing.
representational ability  Piaget's term for capacity to store mental images or symbols of objects and events.
representational mappings  In neo-Piagetian terminology, second stage in development of self-definition, in which a child makes logical connections between aspects of the self but still sees these characteristics in all-ornothing terms.
representational systems  In neo-Piagetian terminology, the third stage in development of self-definition, characterized by breadth, balance, and the integration and assessment of various aspects of the self.
reserve capacity  Ability of body organs and systems to put forth 4 to 10 times as much effort as usual under acute stress; also called organ reserve.
resilient children  Children who weather adverse circumstances, function well despite challenges or threats, or bounce back from traumatic events.
retrieval  Process by which information is accessed or recalled from memory storage.
revolving door syndrome  Tendency for young adults who have left home to return to their parents' household in times of financial, marital, or other trouble.
risk factors  Conditions that increase the likelihood of a negative developmental outcome.
risky drinking  Consuming more than 14 drinks a week or 4 drinks on any single day for men, and more than 7 drinks a week or 3 drinks on any single day for women.
rough-and-tumble play  Vigorous play involving wrestling, hitting, and chasing, often accompanied by laughing and screaming.
sample  Group of participants chosen to represent the entire population under study.
sandwich generation  Middle-aged adults squeezed by competing needs to raise or launch children and to care for elderly parents.
scaffolding  Temporary support to help a child master a task.
schemes  Piaget's term for organized patterns of thought and behavior used in particular situations.
schizophrenia  Mental disorder marked by loss of contact with reality; symptoms include hallucinations and delusions.
school phobia  Unrealistic fear of going to school; may be a form of separation anxiety disorder or social phobia.
scientific method  System of established principles and processes of scientific inquiry, which includes identifying a problem to be studied, formulating a hypothesis to be tested by research, collecting data, analyzing the data, forming tentative conclusions, and disseminating findings.
script  General remembered outline of a familiar, repeated event, used to guide behavior.
secondary aging  Aging processes that result from disease and bodily abuse and disuse and are often preventable.
secondary sex characteristics  Physiological signs of sexual maturation (such as breast development and growth of body hair) that do not involve the sex organs.
secular trend  Trend that can be seen only by observing several generations, such as the trend toward earlier attainment of adult height and sexual maturity, which began a century ago in some countries.
secure attachment  Pattern in which an infant cries or protests when the primary caregiver leaves and actively seeks out the caregiver on his or her return.
selective optimization with compensation (SOC)  Enhancing overall cognitive functioning by using stronger abilities to compensate for those that have weakened.
self-awareness  Realization that one's existence and functioning are separate from those of other people and things.
self-concept  Sense of self; descriptive and evaluative mental picture of one's abilities and traits.
self-conscious emotions  Emotions, such as embarrassment, empathy, and envy, that depend on self-awareness.
self-definition  Cluster of characteristics used to describe oneself.
self-efficacy  Sense of one's capability to master challenges and achieve goals.
self-esteem  The judgment a person makes about his or her self-worth.
self-evaluative emotions  Emotions, such as pride, shame, and guilt, that depend on both self-awareness and knowledge of socially accepted standards of behavior.
self-regulation  A child's independent control of behavior to conform to understood social expectations.
semantic memory  Long-term memory of general factual knowledge, social customs, and language.
senescence  Period of the life span marked by declines in physical functioning usually associated with aging; begins at different ages for different people.
sensitive periods  Times in development when a person is particularly open to certain kinds of experiences.
sensorimotor stage  Piaget's first stage in cognitive development, in which infants learn through senses and motor activity.
sensory memory  Initial, brief, temporary storage of sensory information.
separation anxiety  Distress shown by someone, typically an infant, when a familiar caregiver leaves.
separation anxiety disorder  Condition involving excessive, prolonged anxiety concerning separation from home or from people to whom a person is attached.
sequential study  Study design that combines cross-sectional and longitudinal techniques.
seriation  Ability to order items along a dimension.
sex chromosomes  Pair of chromosomes that determines sex: XX in the normal human female, XY in the normal human male.
sex-linked inheritance  Pattern of inheritance in which certain characteristics carried on the X chromosome inherited from the mother are transmitted differently to her male and female off spring.
sexual abuse  Physically or psychologically harmful sexual activity or any sexual activity involving a child and an older person.
sexually transmitted infections (STIs)  Infections and diseases spread by sexual contact.
sexual orientation  Focus of consistent sexual, romantic, and affectionate interest, either heterosexual, homosexual, or bisexual.
shaken baby syndrome  Form of maltreatment in which shaking an infant or toddler can cause brain damage, paralysis, or death.
single representations  In neo-Piagetian terminology, first stage in development of self-definition, in which children describe themselves in terms of individual, unconnected characteristics and in all-or-nothing terms.
situational compliance  Kochanska's term for obedience of a parent's orders only in the presence of signs of ongoing parental control.
"slow-to-warm-up" children  Children whose temperament is generally mild but who are hesitant about accepting new experiences.
small-for-date (small-for-gestational-age) infants  Infants whose birth weight is less than that of 90 percent of babies of the same gestational age, as a result of slow fetal growth.
social capital  Family and community resources on which a person can draw.
social clock  Set of cultural norms or expectations for the times of life when certain important events, such as marriage, parenthood, entry into work, and retirement, should occur.
social cognition  The ability to understand that others have mental states and to gauge their feelings and actions.
social cognitive theory  Albert Bandura's expansion of social learning theory; holds that children learn gender roles through socialization.
social construction  A concept or practice that may appear natural and obvious to those who accept it, but that in reality is an invention of a particular culture or society.
social-contextual approach  Approach to the study of cognitive development that focuses on environmental influences, particularly parents and other caregivers.
social convoy theory  Theory, proposed by Kahn and Antonucci, that people move through life surrounded by concentric circles of intimate relationships on which they rely for assistance, well-being, and social support.
social interaction model  Model, based on Vygotsky's sociocultural theory, which proposes that children construct autobiographical memories through conversation with adults about shared events.
socialization  Development of habits, skills, values, and motives shared by responsible, productive members of a society.
social learning theory  Theory that behaviors are learned by observing and imitating models. Also called social cognitive theory.
social phobia  Extreme fear and/or avoidance of social situations.
social referencing  Understanding an ambiguous situation by seeking another person's perception of it.
social smiling  Beginning in the 2nd month, newborn infants gaze at their parents and smile at them, signaling positive participation in the relationship.
social speech  Speech intended to be understood by a listener.
sociocultural theory  Vygotsky's theory of how contextual factors affect children's development.
socioeconomic status (SES)  Combination of economic and social factors describing an individual or family, including income, education, and occupation.
socioemotional selectivity theory  Theory, proposed by Carstensen, that people select social contacts on the basis of the changing relative importance of social interaction as a source of information, as an aid in developing and maintaining a self-concept, and as a source of emotional wellbeing.
spermarche  Boy's first ejaculation.
spillover hypothesis  Hypothesis that there is a carryover of cognitive gains from work to leisure that explains the positive relationship between activities in the quality of intellectual functioning.
spontaneous abortion  Natural expulsion from the uterus of an embryo that cannot survive outside the womb; also called miscarriage.
Stanford-Binet Intelligence Scales  Individual intelligence tests for ages 2 and up used to measure fluid reasoning, knowledge, quantitative reasoning, visual-spatial processing, and working memory.
state of arousal  An infant's physiological and behavioral status at a given moment in the periodic daily cycle of wakefulness, sleep, and activity.
Sternberg Triarchic Abilities Test (STAT)  Test that seeks to measure componential, experiential, and contextual intelligence.
stillbirth  Death of a fetus at or after the 20th week of gestation.
storage  Retention of information in memory for future use.
stranger anxiety  Wariness of strange people and places, shown by some infants during the second half of the 1st year.
Strange Situation  Laboratory technique used to study infant attachment.
stress  (1) Physical or psychological demands on a person or organism. (2) Response to physical or psychological demands.
stressors  Perceived environmental demands that may produce stress.
substance abuse  Repeated, harmful use of a substance, usually alcohol or other drugs.
substance dependence  Addiction (physical, or psychological, or both) to a harmful substance.
substantive complexity  Degree to which a person's work requires thought and independent judgment.
sudden infant death syndrome (SIDS)  Sudden and unexplained death of an apparently healthy infant.
survival curves  Curves, plotted on a graph, showing percentages of a population that survive at each age level.
symbolic function  Piaget's term for ability to use mental representations (words, numbers, or images) to which a child has attached meaning.
syntax  Rules for forming sentences in a particular language.
systems of action  Increasingly complex combinations of motor skills, which permit a wider or more precise range of movement and more control of the environment.
tacit knowledge  Sternberg's term for information that is not formally taught or openly expressed but is necessary to get ahead.
telegraphic speech  Early form of sentence use consisting of only a few essential words.
temperament  Characteristic disposition, or style of approaching and reacting to situations.
teratogen  Environmental agent, such as a virus, a drug, or radiation, that can interfere with normal prenatal development and cause developmental abnormalities.
terminal drop  A frequently observed decline in cognitive abilities near the end of life. Also called terminal decline.
thanatology  Study of death and dying.
theory  Coherent set of logically related concepts that seeks to organize, explain, and predict data.
theory of mind  Awareness and understanding of mental processes.
theory of multiple intelligences  Gardner's theory that each person has several distinct forms of intelligence.
theory of sexual selection  Darwin's theory that gender roles developed in response to men's and women's differing reproductive needs.
timing-of-events model  Theoretical model of personality development that describes adult psychosocial development as a response to the expected or unexpected occurrence and timing of important life events.
trait models  Theoretical models of personality development that focus on mental, emotional, temperamental, and behavioral traits, or attributes.
transduction  Piaget's term for a preoperational child's tendency to mentally link particular phenomena, whether or not there is logically a causal relationship.
transitive inference  Understanding the relationship between two objects by knowing the relationship of each to a third object.
triangular theory of love  Sternberg's theory that patterns of love hinge on the balance among three elements: intimacy, passion, and commitment.
triarchic theory of intelligence  Sternberg's theory describing three elements of intelligence: componential, experiential, and contextual.
turning points  Psychological transitions that involve significant change or transformation in the perceived meaning, purpose, or direction of a person's life.
two-way (dual-language) learning  Approach to second-language education in which English speakers and non-English speakers learn together in their own and each other's languages.
typological approach  Theoretical approach that identifies broad personality types, or styles.
ultrasound  Prenatal medical procedure using high-frequency sound waves to detect the outline of a fetus and its movements, so as to determine whether a pregnancy is progressing normally.
variable-rate theories  Theories that explain biological aging as a result of processes that vary from person to person and are influenced by both the internal and the external environment; sometimes called error theories.
violation-of-expectations  Research method in which dishabituation to a stimulus that conflicts with experience is taken as evidence that an infant recognizes the new stimulus as surprising.
visible imitation  Imitation with parts of one's body that one can see.
visual cliff  Apparatus designed to give an illusion of depth and used to assess depth perception in infants.
visual guidance  Use of the eyes to guide movements of the hands or other parts of the body.
visually based retrieval  Process of retrieving the sound of a printed word when seeing the word as a whole.
visual preference  Tendency of infants to spend more time looking at one sight than another.
visual recognition memory  Ability to distinguish a familiar visual stimulus from an unfamiliar one when shown both at the same time.
vital capacity  Amount of air that can be drawn in with a deep breath and expelled.
Wechsler Adult Intelligence Scale (WAIS)  Intelligence test for adults that yields verbal and performance scores as well as a combined score.
Wechsler Intelligence Scale for Children (WISC-IV)  Individual intelligence test for school-age children, which yields verbal and performance scores as well as a combined score.
Wechsler Preschool and Primary Scale of Intelligence, Revised (WPPSI-III)  Individual intelligence test for children ages 2½ to 7 that yields verbal and performance scores as well as a combined score.
whole-language approach  Approach to teaching reading that emphasizes visual retrieval and use of contextual clues.
withdrawal of love  Disciplinary strategy that involves ignoring, isolating, or showing dislike for a child.
working memory  Short-term storage of information being actively processed.
zone of proximal development (ZPD)  Vygotsky's term for the difference between what a child can do alone and what the child can do with help.
zygote  One-celled organism resulting from fertilization.







Human DevelopmentOnline Learning Center

Home > Glossary