a progressive and irreversible brain disorder characterized by gradual deterioration of memory, reasoning, language, and finally, phisical funtioning.

the fear of strangers that infants begin to display at about 8 months of age.

in this study the same people are tested and retested over a period of years.

a branch of psychology that studies human development in phsical, cognitive, and social change perspectives.

in Piaget's theory normally begins about ageDuring this stage people begin to think logically about abstract concepts.

one's accumulated acknowledge and verbal skills; tends fo increase with age

agents, such as chemicals and viruses, that can reach the embryo or fetus during prenatal development and cause harm.

in Piaget's theory lasts from about 2 to 6 or 7 years of age. During this stage, language development is rapid, but the child is unable to understand the mental operations of concrete logic.

the first menstrual period.

the principle that properties such as number, volume, and mass remain constant despite changes in the forms of objects; it is acquired during the concrete operational stage.

the developing human organism from 9 weeks after conception to birth.

a disorder that appears in childhood and is marked by deficient communication, social interaction, and understanding of others' states of mind.

in Erikson's theory, the ability to form close, loving relationships; a primary developmental task in late adolescence and early adulthood.

a baby's tendency, when touched on the cheek, to turn toward the touch, open the mouth, and search for the nipple.

refers to those aspects of intellectual ability, such as vocabulary and general knowledged that reflect accumulated learning. Crystallized intelligence tends to increase with age.

the fertilized egg; it enters a 2-week period of rapid cell division and develops into an embryo

the time of natural cessation of menstruation; also refers to the biological changes a woman experiences as her ability to reproduce declines.

refers to a person's ability to reason speedily and abstractly. Fluid intelligence tends to decline with age.

the process by which certain animals form attachments early in life, usually during a limited critical period.

people's ideas about their own and others' mental states—about their feelings, perceptions, and thoughts and the behavior these might predict.

the early adolescent period of sexual maturation, during which a person becomes capable of reproduction.

according to Erikson is a sense that the world is predictable and trustworthy - a concept that infants form if their needs are met by responsive caregiving.

in Piaget's theory refers to the difficulty that preoperational children have in considing another's viewpoint. "Ego" means "self" erring and "centrism" indicates "in the center"; the preoperational child is "self-centered."

are mental concepts that organize and interpret information. They are found in Piaget's theory of cognitive development

this refers to the life stage from puberty to independent adulthood, denoted physically by a growth spurt and maturation of primary and secondary sex characteristics, cognitively by the onset of formal operational thought, and socially by the formation of identity.

the stage lasting from about ages 6 or 7 to 11, children can think logically about concrete events and objects.

in this study people of different ages are compared with one another.

one's sense of self; according to Erikson, the adolescent's task is to solidify a sense of self by testing and integrating various roles.

refers to interpreting a new experience in terms of an existing schema.In Piaget's theory.

an emotional tie with another person, shown in young children by their seeking closeness to a caregiver and showing distress on separation.

a syndrome that refers to the physical and cognitive abnormalities that heavy drinking by a pregnant woman may cause in the developing child.