absent grief A situation in which mourners do not grieve, either because other people do not allow grief to be expressed or because the mourners do not allow themselves to feel sadness.

acceleration Educating gifted children alongside other children of the same mental, not chronological, age.

accommodation The restructuring of old ideas to include new experiences.

achievement test A measure of mastery or proficiency in reading, mathematics, writing, science, or some other subject.

active euthanasia A situation in which someone takes action to bring about another person’s death, with the intention of ending that person’s suffering.

activities of daily life (ADLs) Typically identified as five tasks of self-care that are important to independent living: eating, bathing, toileting, dressing, and transferring from a bed to a chair. The inability to perform any of these tasks is a sign of frailty.

activity theory The view that elderly people want and need to remain active in a variety of social spheres—with relatives, friends, and community groups—and become withdrawn only unwillingly, as a result of ageism.

acute illness An illness that is sudden and severe.

adolescence-limited offender A person whose criminal activity stops by age 21.

adolescent egocentrism A characteristic of adolescent thinking that leads young people (ages 10 to 13) to focus on themselves to the exclusion of others.

adoption A legal proceeding in which an adult or couple, sometimes a relative, is granted the joys and obligations of being that child’s parent(s).

adrenal glands Two glands, located above the kidneys, that produce hormones (including the “stress hormones” epinephrine [adrenaline] and norepinephrine).

advance directives Any description of what people want to happen as they die and after they die. This can include medical measures, choosing whom to allow as visitors, funeral arrangements, cremation, and so on.

affordance An opportunity for perception and interaction that is offered by a person, place, or object in the environment.

age in place To remain in the same home and community in later life, adjusting but not leaving when health fades.

age of viability The age (about 22 weeks after conception) at which a fetus might survive outside the mother’s uterus if specialized medical care is available.

ageism A prejudice whereby people are categorized and judged solely on the basis of their chronological age.

aggressive-rejected Rejected by peers because of antagonistic, confrontational behavior.

allele A variation that makes a gene different in some way from other genes for the same characteristics. Many genes never vary; others have several possible alleles.

allocare The care of children by people other than their biological parents.

allostasis A dynamic body adjustment, related to homeostasis, that affects overall physiology over time. The main difference is that homeostasis requires an immediate response, whereas allostasis requires longer-term adjustment.

Alzheimer disease (AD) The most common cause of dementia, characterized by gradual deterioration of memory and personality and marked by the formation of plaques of beta-amyloid protein and tangles of tau in the brain. (Sometimes called senile dementia of the Alzheimer type.)

amygdala A tiny brain structure that registers emotions, particularly fear and anxiety.

analytic intelligence A form of intelligence that involves such mental processes as abstract planning, strategy selection, focused attention, and information processing, as well as verbal and logical skills.

analytic thought Thought that results from analysis, such as a systematic ranking of pros and cons, risks and consequences, possibilities and facts. Analytic thought depends on logic and rationality.

andropause A term coined to signify a drop in testosterone levels in older men, which normally results in reduced sexual desire, erections, and muscle mass. (Also called male menopause.)

animism The belief that natural objects and phenomena are alive.

anorexia nervosa An eating disorder characterized by self-starvation. Affected individuals voluntarily undereat and often overexercise, depriving their vital organs of nutrition. Anorexia can be fatal.

anoxia A lack of oxygen that, if prolonged, can cause brain damage or death.

antipathy Feelings of dislike or even hatred for another person.

antisocial behavior Actions that are deliberately hurtful or destructive to another person.

antithesis A proposition or statement of belief that opposes the thesis; the second stage of the process of dialectical thinking.

Apgar scale A quick assessment of a newborn’s health. The baby’s color, heart rate, reflexes, muscle tone, and respiratory effort are given a score of 0, 1, or 2 twice—at one minute and five minutes after birth—and each time the total of all five scores is compared with the maximum score of 10 (rarely attained).

apprenticeship in thinking Vygotsky’s term for how cognition is stimulated and developed in people by more skilled members of society.

aptitude The potential to master a specific skill or to learn a certain body of knowledge.

assimilation The reinterpretation of new experiences to fit into old ideas.

assisted reproductive technology (ART) A general term for the techniques designed to help infertile couples conceive and then sustain a pregnancy.

asthma A chronic disease of the respiratory system in which inflammation narrows the airways from the nose and mouth to the lungs, causing difficulty in breathing. Signs and symptoms include wheezing, shortness of breath, chest tightness, and coughing.

attachment According to Ainsworth, “an affectional tie” that an infant forms with a caregiver—a tie that binds them together in space and endures over time.

attention-deficit/hyperactivity disorder (ADHD) A condition characterized by a persistent pattern of inattention and/or by hyperactive or impulsive behaviors; ADHD interferes with a person’s functioning or development.

authoritarian parenting An approach to child rearing that is characterized by high behavioral standards, strict punishment for misconduct, and little communication from child to parent.

authoritative parenting An approach to child rearing in which the parents set limits but listen to the child and are flexible.

autism spectrum disorder A developmental disorder marked by difficulty with social communication and interaction—including difficulty seeing things from another person’s point of view—and restricted, repetitive patterns of behavior, interests, or activities.

automatic processing Thinking that occurs without deliberate, conscious thought. Experts process most tasks automatically, saving conscious thought for unfamiliar challenges.

automatization A process in which repetition of a sequence of thoughts and actions makes the sequence routine, so that it no longer requires conscious thought.

autonomy versus shame and doubt Erikson’s second crisis of psychosocial development. Toddlers either succeed or fail in gaining a sense of self-rule over their actions and their bodies.

average life expectancy The number of years the average newborn in a particular population group is likely to live.

avoidant coping A method of responding to a stressor by ignoring, forgetting, or hiding it.

axon A fiber that extends from a neuron and transmits electrochemical impulses from that neuron to the dendrites of other neurons.