3.3.1 Piaget's theory of cognitive developmen

3.3.1 Piaget's theory of cognitive development

The most well-known and influential theory of cognitive development is that of French psychologist Jean Piaget (1896–1980). Piaget's theory, first published in 1952, grew out of decades of extensive observation of children, including his own, in their natural environments as opposed to the laboratory experiments of the behaviorists. Although Piaget was interested in how children reacted to their environment, he proposed a more active role for them than that suggested by learning theory. He envisioned a child's knowledge as composed of schemas, basic units of knowledge used to organize past experiences and serve as a basis for understanding new ones.

Schemas are continually being modified by two complementary processes that Piaget termed assimilation and accommodation. Assimilation refers to the process of taking in new information by incorporating it into an existing schema. In other words, people assimilate new experiences by relating them to things they already know. On the other hand, accommodation is what happens when the schema itself changes to accommodate new knowledge. According to Piaget, cognitive development involves an ongoing attempt to achieve a balance between assimilation and accommodation that he termed equilibration.

At the center of Piaget's theory is the principle that cognitive development occurs in a series of four distinct, universal stages, each characterized by increasingly sophisticated and abstract levels of thought. These stages always occur in the same order, and each builds on what was learned in the previous stage. They are as follows:

Sensorimotor stage (infancy): In this period, which has six sub-stages, intelligence is demonstrated through motor activity without the use of symbols. Knowledge of the world is limited, but developing, because it is based on physical interactions and experiences. Children acquire object permanence at about seven months of age (memory). Physical development (mobility) allows the child to begin developing new

  • intellectual abilities. Some symbolic (language) abilities are developed at the end of this stage.
  • Pre-operational stage (toddlerhood and early childhood): In this period, which has two sub stages, intelligence is demonstrated through the use of symbols, language use matures, and memory and imagination are developed, but thinking is done in a non-logical, non-reversible manner. Egocentric thinking predominates.
  • Concrete operational stage (elementary and early adolescence): In this stage, characterized by seven types of conservation (number, length, liquid, mass, weight, area, and volume), intelligence is demonstrated through logical and systematic manipulation of symbols related to concrete objects. Operational thinking develops (mental actions that are reversible). Egocentric thought diminishes.
  • Formal operational stage (adolescence and adulthood): In this stage, intelligence is demonstrated through the logical use of symbols related to abstract concepts. Early in the period there is a return to egocentric thought. Only 35 percent of high school graduates in industrialized countries obtain formal operations; many people do not think formally during adulthood.

The most significant alternative to the work of Piaget has been the information-processing approach, which uses the computer as a model to provide new insight into how the human mind receives, stores, retrieves, and uses information. Researchers using information-processing theory to study cognitive development in children have focused on areas such as the gradual improvements in children's ability to take in information and focus selectively on certain parts of it and their increasing attention spans and capacity for memory storage. For example, researchers have found that the superior memory skills of older children are due in part to memorization strategies, such as repeating items in order to memorize them or dividing them into categories.


As soon as they are born, infants begin learning to use their senses to explore the world around them. Most newborns can focus on and follow moving objects, distinguish the pitch and volume of sound, see all colors and distinguish their hue and brightness, and start anticipating events, such as sucking at the sight of a nipple. By three months old, infants can recognize faces; imitate the facial expressions of others, such as smiling and frowning; and respond to familiar sounds.

At six months of age, babies are just beginning to understand how the world around them works. They imitate sounds, enjoy hearing their own voice, recognize parents, fear strangers, distinguish between animate and inanimate

they drop an object, they can pick it up again. At four to seven months, babies can recognize their names.

By nine months, infants can imitate gestures and actions, experiment with the physical properties of objects, understand simple words such as "no," and understand that an object still exists even when they cannot see it. They also begin to test parental responses to their behavior, such as throwing food on the floor. They remember the reaction and test the parents again to see if they get the same reaction.

At 12 months of age, babies can follow a fast moving object; can speak two to fours words, including "mama" and "papa"; imitate animal sounds; associate names with objects; develop attachments to objects, such as a toy or blanket; and experience separation anxiety when away from their parents. By 18 months of age, babies are able to understand about 10–50 words; identify body parts; feel a sense of ownership by using the word "my" with certain people or objects; and can follow directions that involve two different tasks, such as picking up toys and putting them in a box.


Between 18 months to three years of age, toddlers have reached the "sensorimotor" stage of Piaget's theory of cognitive development that involves rudimentary thought. For instance, they understand the permanence of objects and people, visually follow the displacement of objects, and begin to use instruments and tools. Toddlers start to strive for more independence, which can present challenges to parents concerned for their safety. They also understand discipline and what behavior is appropriate and inappropriate, and they understand the concepts of words like "please" and "thank you."

Two-year-olds should be able to understand 100 to 150 words and start adding about ten new words per day. Toddlers also have a better understanding of emotions, such as love, trust, and fear. They begin to understand some of the ordinary aspects of everyday life, such as shopping for food, telling time, and being read to.


Preschoolers, ages three to six, should be at the "preoperational" stage of Piaget's cognitive development theory, meaning they are using their imagery and memory skills. They should be conditioned to learning and memorizing, and their view of the world is normally very self-centered. Preschoolers usually have also developed their social interaction skills, such as playing and cooperating with other children their own age. It is normal for preschoolers to test the limits of their cognitive abilities, and they learn negative concepts and actions, such as talking back to adults, lying, and bullying. Other cognitive development in preschoolers are developing an increased attention span, learning to read, and developing structured routines, such as doing household chores.

School age

Younger school-age children, six to 12 years old, should be at the "concrete operations" stage of Piaget's cognitive development theory, characterized by the ability to use logical and coherent actions in thinking and solving problems. They understand the concepts of permanence and conservation by learning that volume, weight, and numbers may remain constant despite changes in outward appearance. These children should be able to build on past experiences, using them to explain why some things happen. Their attention span should increase with age, from being able to focus on a task for about 15 minutes at age six to an hour by age nine.

Adolescents, ages 12 through 18, should be at the "formal operations" stage of Piaget's cognitive development theory. It is characterized by an increased independence for thinking through problems and situations. Adolescents should be able to understand pure abstractions, such as philosophy and higher math concepts. During this age, children should be able to learn and apply general information needed to adapt to specific situations. They should also be able to learn specific information and skills necessary for an occupation. A major component of the passage through adolescence is a cognitive transition. Compared to children, adolescents think in ways that are more advanced, more efficient, and generally more complex. This ability can be seen in five ways.

First, during adolescence individuals become better able than children to think about what is possible, instead of limiting their thought to what is real. Whereas children's thinking is oriented to the here and now—that is, to things and events that they can observe directly—adolescents are able to consider what they observe against a backdrop of what is possible; they can think hypothetically.

Second, during the passage into adolescence, individuals become better able to think about abstract ideas. For example, adolescents find it easier than children to comprehend the sorts of higher-order, abstract logic inherent in puns, proverbs, metaphors, and analogies. The adolescent's greater facility with abstract thinking also permits the application of advanced reasoning and logical processes to social and ideological matters. This is clearly seen in the adolescent's increased facility and interest in thinking about interpersonal relationships, politics, philosophy, religion, and morality.

Third, during adolescence individuals begin thinking more often about the process of thinking itself, or metacognition. As a result, adolescents may display increased introspection and self-consciousness. Although improvements in metacognitive abilities provide important intellectual advantages, one potentially negative byproduct of these advances is the tendency for adolescents to develop a sort of egocentrism, or intense preoccupation with the self.

A fourth change in cognition is that thinking tends to become multidimensional, rather than limited to a single issue. Whereas children tend to think about things one aspect at a time, adolescents can see things through more complicated lenses. Adolescents describe themselves and others in more differentiated and complicated terms and find it easier to look at problems from multiple perspectives. Being able to understand that people's personalities are not one-sided or that social situations can have different interpretations depending on one's point of view permits the adolescent to have far more sophisticated and complicated relationships with other people.

Finally, adolescents are more likely than children to see things as relative, rather than absolute. Children tend to see things in absolute terms—in black and white. Adolescents, in contrast, tend to see things as relative. They are more likely to question others' assertions and less likely to accept facts as absolute truths. This increase in relativism can be particularly exasperating to parents, who may feel that their adolescent children question everything just for the sake of argument. Difficulties often arise, for example, when adolescents begin seeing their parents' values as excessively relative.

(Table by GGS Information Services.)

Cognitive development



SOURCE : Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, 5th ed . and Child Development Institute, http://www.childdevelopmentinfo.com.

One month

Watches person when spoken to.

Two months

Smiles at familiar person talking. Begins to follow moving person with eyes.

Four months

Shows interest in bottle, breast, familiar toy, or new surroundings.

Five months

Smiles at own image in mirror. Looks for fallen objects.

Six months

May stick out tongue in imitation. Laughs at peekaboo game. Vocalizes at mirror image. May act shy around strangers.

Seven months

Responds to own name. Tries to establish contact with a person by cough or other noise.

Eight months

Reaches for toys out of reach. Responds to "no."

Nine months

Shows likes and dislikes. May try to prevent face-washing or other activity that is disliked. Shows excitement and interest in foods or toys that are well-liked.

Ten months

Starts to understand some words. Waves bye-bye. Holds out arm or leg for dressing.

Eleven months

Repeats performance that is laughed at. Likes repetitive play. Shows interest in books.

Twelve months

May understand some "where is...?" questions. May kiss on request.

Fifteen months

Asks for objects by pointing. Starting to feed self. Negativism begins.

Eighteen months

Points to familiar objects when asked "where is...?" Mimics familiar adult activities. Know some body parts. Obeys two or three simple orders.

Two years

Names a few familiar objects. Draws with crayons. Obeys found simple orders. Participates in parallel play.

Two-and-a-half years

Names several common objects. Begins to take interest in sex organs. Gives full names. Helps to put things away. Peak of negativism.

Three years

Constantly asks questions. May count to 10. Begins to draw specific objects. Dresses and undresses doll. Participates in cooperative play. Talks about things that have happened.

Four years

May make up silly words and stories. Beginning to draw pictures that represent familiar things. Pretends to read and write. May recognize a few common words, such as own name.

Five years

Can recognize and reproduce many shapes, letters, and numbers. Tells long stories. Begins to understand the difference between real events and make-believe ones. Asks meaning of words.