Developmental Psychology - How Children Become Adults

There are also developmental stages associated with adulthood. Developmental psychology is the study of the growth and maturation of the individual over an extended span of time. Child psychology is a subset of developmental psychology. It concerns itself primarily with the study of the individual from birth to the beginning of adolescence (usually around the age of twelve or thirteen). Adolescent psychology is also a subset of developmental psychology. It concerns itself primarily with the study of the individual from the beginning of adolescence to its end (usually around the age of eighteen).

Biological Aspects of Development: From Fertilized Egg to Infant

A chromosome is a rodlike structure that contains genes. A chromosome is so named because it is capable of picking up a dye, making the structure visible under a microscope. Chromo refers to color, and soma refers to body. Thus a chromosome is a “colored body.”

A gene is the basic unit of heredity. It is made up of strands of deoxyribonucleic acid (DNA), a complex organic molecule with the unique ability to replicate itself. It is the genes that do all of the active work associated with hereditary influence. The relationship of a chromosome to a group of genes is similar to the relationship of a ship to its crew. The chromosome is the ship. The genes are the members of the crew.

There are four stages associated with conception and birth: (1) zygote, (2) embryo, (3) fetus, and (4) neonate. When a sperm and an ovum unite to form a fertilized egg, the new being is called a zygote. The stage of the zygote lasts for one week. During this stage the zygote develops rapidly from a single cell to a large group of cells. A zygote may be imagined as a ball of cells without differentiation.

From one week to seven weeks, the new being is called an embryo. As the cells continue to divide and replicate themselves, some differentiation begins to take place. Three basic embryonic layers emerge: The ectoderm is the outer layer of cells, and it will become the sense organs, skin, and nervous system. The mesoderm is the middle layer of cells, and it will become the heart, bones, and muscles. The endoderm is the internal layer of cells, and it will become the stomach, intestines, and lungs.

From seven weeks to birth, the new being is called a fetus. Fetal development is rich and complex. The cells continue to divide, and they become specialized in their structures and functions. Brain cells (neurons), skin cells, hair cells, fat cells, and many other kinds of cells form. The head, limbs, fingers and toes, and other features of the body appear. In the typical case, the stage of the fetus lasts a little over seven months, making the total time from conception to birth about nine months.

Freud’s Theory of Psychosexual Development: From the Oral to the Genital Stage

According to Freud, there are five stages in psychosexual development. Psychosexual development refers to the development of a sexual identity, attitudes toward sexual behavior, and emotional reactions to sexual stimuli. Sexual development, in Freud’s view, is much more than biological. Identity, attitudes, and emotional reactions are psychological in nature. That is why Freud used the term psychosexual instead of simply sexual to refer to the kind of development he wanted to study.

The five stages of psychosexual development are:

1. The oral stage lasts for about two years (infancy). During this stage the infant obtains a substantial amount of pleasure from sucking, biting, chewing, and so forth.
2. The anal stage lasts for about one or two years (the stage of the toddler). During the anal stage the toddler obtains a substantial amount of pleasure from, at times, withholding fecal matter and, at other times, expelling it. Note that this stage coincides with the time at which most children are toilet trained.
3. The phallic stage lasts for about three years (the stage of the preschooler). During the phallic stage the preschooler, according to Freud, obtains a substantial amount of pleasure from self-stimulation of the phallus. The phallus in the male is the penis. In the female it is the clitoris. The phallic stage ends at about the age of six.
4. The latency stage lasts for about six years. It begins at age six or seven and ends at age twelve or thirteen. In effect, it ends when puberty begins. The libido has migrated from the oral to the anal to the phallic zone. Now it goes underground and becomes, to surface appearance, dormant. The libido goes underground not because of a lack of biological maturation, but because of psychological conflict. Freud suggested that the child has a certain amount of dawning sexual desire and tends to make the parent of the opposite sex the focus of this desire. However, due to moral development, guilt sets in and the libido goes into hiding. It is repressed to an unconscious level.
5. The genital stage begins at twelve or thirteen and continues throughout adulthood. With puberty, biological maturation can no longer be denied. The repression lifts and the individual becomes intensely conscious of sexual interest. Libido makes a final shift from the phallus to a more general interest in the opposite sex. In normal development, the individual transfers sexual interest away from the parent and toward potential partners who are not members of the family.

Erikson’s Theory of Psychosocial Development: From Trust to Integrity

According to Erik Erikson (1902-1994), there are eight stages in psychosocial development:

1. Trust versus mistrust is associated with infancy (birth to two years old). An infant with a sense of trust tends to thrive and expects good things to happen.
2. Autonomy versus shame and doubt is associated with toddlerhood (two to three years old). A toddler with a sense of autonomy will be interested in exploring the immediate world and display an interest in novel stimulation.
3. Initiative versus guilt is associated with the preschool period (three to six years old). A preschooler with a sense of initiative will be likely to start a project and see it through to completion.
4. Industry versus inferiority is associated with middle childhood (six to twelve years old). A child with a sense of industry will show an interest in school, study, complete homework, agree to do reasonable chores, and in general display responsible behavior.
5. Identity versus role confusion is associated with adolescence (twelve to eighteen years old). An adolescent with an identity has a sense of direction in life.
6. Intimacy versus isolation is associated with young adulthood. This starts when adolescence is over, usually around the age of eighteen.
7. Generativity versus self-absorption is associated with adulthood. An adult with the trait of generativity is capable of productive work.
8. Integrity versus despair is associated with old age. An older person with the
9. trait of integrity can face approaching death with a certain amount of acceptance.

Piaget’s Theory of Cognitive Development: From Magical Thinking to Logical Thinking

Jean Piaget (1896–1980), used to study the child’s mind is called the phenomenological method.

According to Piaget, there are four stages of cognitive development:

1. The sensorimotor stage is associated with infancy (birth to two years old). During this stage the infant has consciousness, but not self-consciousness.
2. The preoperational stage is associated with toddlerhood and the preschool age (two to seven years old). The term preoperational is used to suggest that during this stage the child has not yet grasped the concept of cause and effect.
3. The concrete operations stage is associated with middle childhood (seven to twelve years old). The child at this stage can think in terms of cause and effect.
4. The formal operations stage is associated with adolescence and adulthood. (Adolescence begins at twelve or thirteen years old). The formal operations stage is characterized by the ability to think in abstract terms.

Parental Style: Becoming an Effective Parent

Whether it be psychosexual, psychosocial, cognitive, or moral, development is greatly influenced what parents say and do. The general approach taken toward child rearing by a parent is called parental style. Research conducted by developmental psychologists such as Stanley Coopersmith and Diane Baumrind, both affiliated with the University of California, suggests that there are two primary dimensions of parental style. These are:

The authoritarian-permissive dimension consists of bipolar opposites. At the one extreme, parents who manifest an authoritarian style are highly controlling, demanding, possessive, and overprotective. At the other extreme, parents who manifest a permissive style are easygoing, overly agreeable, detached, and easily manipulated by the child or adolescent. Such parents tend to avoid setting well-defined limits on behavior.

The accepting-rejecting dimension also consists of bipolar opposites. At the one extreme, parents who manifest an accepting style provide the child with unconditional love, meaning that love is not withdrawn when a child’s behavior is unacceptable. The child is loved for being himself or herself, and affection does not stop just because the parent is sometimes disappointed in something the child has done. There is much confusion about this particular point. Unconditional love does not mean unconditional acceptance of all behavior. It is possible to reject unacceptable behavior without rejecting the whole person.

The two dimensions generate five distinct categories of parental style:

1. authoritarian-accepting,
2. permissive-accepting,
3. authoritarian-rejecting,
4. permissive-rejecting,
5. democratic-accepting.