A theory provides a framework of general principles to guide research and to explain observations. Each of the five major developmental theories—
Theories are neither true nor false. They are not facts; they suggest hypotheses to be tested. Good theories are practical: They aid inquiry, interpretation, and daily life.
A norm is a usual standard of behavior. Norms are not theories, although they may result from theories if a theory suggests that a certain behavior is proper. Norms are not necessarily good or bad, although sometimes differences from the norm are falsely considered deficits.
Psychoanalytic theory emphasizes that human actions and thoughts originate from unconscious impulses and childhood conflicts. Freud theorized that sexual urges arise during three stages of childhood development—
Erikson described psychosocial, not psychosexual, stages. He described eight successive stages of development, each involving a crisis that must be resolved as people mature within their context. Societies, cultures, and family members shape each person’s development.
All psychoanalytic theories stress the legacy of childhood. According to Freud, conflicts associated with children’s erotic impulses have a lasting impact on adult personality. Erikson thought that the resolution of each crisis affects adult development.
Behaviorists, or learning theorists, believe that scientists should study observable and measurable behavior. Behaviorism emphasizes conditioning—
In classical behaviorism, there are two basic kinds of learning. One is classical conditioning, which describes the learning that occurs when one stimulus is linked to another. The other kind is operant conditioning, when the reinforcement or punishment that follows an action guides future behavior.
Social learning theory recognizes that people learn by observing others. Children are particularly susceptible to social learning, as they model their behavior, first after their parents and then after popular peers and famous people.
Cognitive theorists believe that thoughts and beliefs powerfully affect attitudes, actions, and perceptions.
Piaget proposed four age-
Information processing focuses on each aspect of cognitive input, processing, and output. Neuroscience discoveries about how the brain functions have been particularly interesting for information processing theories.
Sociocultural theory explains human development in terms of the guidance, support, and structure provided by knowledgeable members of the society through culture and mentoring.
Vygotsky described how learning occurs through social interactions, in which mentors guide learners through their zone of proximal development.
The universal perspective focuses on the shared impulses and common needs of all humanity. At their core, all humans are far more alike than different.
The two leaders of humanism—
Evolutionary theory contends that contemporary humans inherit genetic tendencies that have fostered survival and reproduction of the human species for tens of thousands of years. Through selective adaptation, human genes are the underlying reason for many human behaviors, including gender differences, mental illness, and family bonds.
Psychoanalytic, behavioral, cognitive, sociocultural, and universal theories have aided our understanding of human development, yet no single theory describes the full complexity and diversity of human experience. Most developmentalists are eclectic, drawing upon many theories.
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