What is cognitive development?

Physical and Psychological Factors

The mental capabilities and skills of humans develop gradually over a period of time from birth through adolescence. As a child ages, the quality of the processes by which he or she responds to and adapts thinking to particular situations and evaluates, plans, and solves problems changes over time.

In childhood, the
brain develops very rapidly. At birth, the human brain already weighs about 25 percent of its adult weight. By six months of age, this figure is 50 percent. By the age of five, the child’s brain has achieved 90 percent of its eventual weight. While the basic structure of the brain is genetically and biologically determined, environment and experience play a significant role in the development of cognition. Children’s biological constitutions may affect the way in which they interact with and respond to their environment.

According to the Swiss psychologist
Jean Piaget (1896–1980), the cognitive growth of all children follows a universal or holistic pattern of development through infancy, childhood, and adolescence. The thought processes of young children are less mature and complex than those of older children, and as children grow and experience life, their cognitive structures become more sophisticated, as well as qualitatively different from those of children in earlier or later stages of development. Cognitive structures, or “schemes” as Piaget called them, are thought patterns that children construct to explain, understand, or interpret their experiences. When children’s schemes or thought processes are in harmony with their environment, they experience cognitive equilibrium. When children encounter new and puzzling events or objects, they are in a state of imbalance or disequilibrium and must achieve equilibrium via a process called equilibration. This process consists of adapting or adjusting one’s existing knowledge or mental structures to the new situation, thus constructing more complex and sophisticated thought structures. Adaptation takes place through the processes of assimilation and accommodation.

Assimilation refers to the process of attempting to explain a new experience in terms of existing schemes. For example, a child who sees a pony for the first time may call it a “kitty” because a cat is the existing model of that child for four-legged animals. Noticing that there are differences between the scheme of a cat and the reality of the pony, however, the child soon attempts to modify existing mental structures to fit the new experience. This process of modification is accommodation. Through assimilation and accommodation, children organize their knowledge into schemes that better explain their observations.

Piaget’s theory of cognitive development, with its emphasis on continuous and active organization and adaptation involving assimilation and accommodation, implies that children actively construct their own knowledge. This construction is based on the child’s current stage of cognitive development: Piaget proposed that all children in a specific, universal cognitive stage construct similar interpretations of similar experiences.

According to Piaget, cognitive development can be divided into four major stages. The order in which these stages occur is universal, and all individuals must experience each stage. No stage can be skipped, although the rates at which children go through a stage may vary. The basis for Piaget’s insistence on the unvarying sequence of cognitive stages is a concept known as epigenesis, which he used to explain the gradual development of thinking processes. Each new structure or cognitive skill is based on and develops from an earlier one. Hence, each stage, and each structure within each stage, is necessary for the development of new, more advanced structures. Piaget called this feature of development “hierarchization.”

The four stages of cognitive development identified by Piaget are the sensorimotor stage (up to age two), the preoperational stage (two to seven years of age), the concrete operations stage (seven to eleven years of age), and the formal operations stage (age eleven and up).

During the sensorimotor stage, children act upon their environment and acquire knowledge of it through their senses and motor activities. In the first two years, cognition progresses from reflexive actions, such as sucking and grasping, to primitive symbolic functions or representation, such as language use and symbolic play. The sensorimotor stage can be further divided into six substages. Substage 1 lasts from birth to one month and centers on exercising basic reflexes, including eye movements, sound orientation, and vocalization, and assimilating and accommodating objects into reflexive schemes. Substage 2, from one to four months, consists of simple repetitive actions, such as thumb sucking, which are discovered by chance and acquired through repeated trials. Piaget called these actions primary circular reactions. Substage 3 appears between four and eight months of age. Piaget named this period secondary circular reactions. Infants notice stimulating events in the environment beyond their bodies—such as a noise made by squeezing a toy or a movement caused by touching an object—and attempt to re-create the events.

Between eight and twelve months of age, infants experience substage 4, or the coordination of secondary schemes. This means that infants can use two already acquired schemes to reach a simple goal. For example, they are able to remove an object to grasp a hidden toy. These early coordinations reflect intentional behavior and simple problem solving. Tertiary circular reactions are characteristic of substage 5, appearing between the ages of twelve and eighteen months. Infants display curiosity, experiment actively, and find new ways of solving problems. Their behaviors are goal-directed but are carried out through trial and error. Substage 6, from eighteen to twenty-four months, reflects inner experimentation or new mental combinations. The infant now displays symbolic functioning through language, imagery, and symbolic play. Children also begin to acquire a sense of cause and effect.

During the sensorimotor stage, children develop the ability to imitate. Piaget believed that novel actions could be imitated by infants around eight to twelve months of age and needed much practice. The ability to imitate absent models, called deferred imitation, appears between twelve and twenty-four months of age.

Another important milestone of the sensorimotor stage is the development of a sense of object permanence. Before the age of four months, objects are of interest to infants only if they can be experienced by the senses. They lose interest in objects that are hidden; such objects no longer exist for them. Between four and eight months of age, they may retain interest in partially hidden objects, and by twelve to eighteen months of age, the concept of objects is stronger. The idea that objects have permanence even when not seen appears around the age of eighteen months, when children can represent objects mentally.

The preoperational stage, the second of Piaget’s stages of cognitive development, occurs between the ages of two and seven. During this stage, children increase their use of words and images to represent objects and experiences. Piaget called this stage “preoperational” because he believed that children had not yet achieved “operations,” or cognitive schemes to think logically. The preoperational stage can further be divided into a preconceptual period (two to four years of age) and an intuitive period (four to seven years of age).

Characteristics of the preconceptual period include the development of symbolic representation, expressed through developing language and pretend play. Children in this stage demonstrate animism; that is, they attribute life to nonliving things. They are egocentric, seeing the world as revolving around themselves and having difficulty in understanding other points of view.

Although still egocentric during the intuitive period, children are less so than before. Piaget argued that they also display centered thinking, or the capacity to classify objects according to one feature or attribute even though several may be evident. Children in this stage find it hard to conserve, or understand that a substance or object’s properties can remain unaltered even when its appearance changes. They cannot reverse actions mentally, such as realizing that water poured from a tall glass into a flat dish is the same amount of water and would look as high as before if poured back into the glass.

In the concrete operations stage, between the ages of seven and eleven, children’s cognitive structures develop to include operations that help them think more competently and logically about objects and events experienced. Children are less egocentric; are able to classify, sequence, and quantify more efficiently; and display skills of conservation and reversibility. Piaget believed, however, that children are still unable to hypothesize or think about abstract concepts during this stage.

From eleven years onward, children enter the formal operations stage. They can hypothesize and reason inductively about abstract concepts such as religion, goodness, or beauty. According to Piaget, this transition from concrete to formal operations is very gradual. He also suggested that many adults reason at the formal operations level only if a problem is important or interesting to them.

Another approach to cognitive development compares individuals as information-processing systems to computers. The hardware in humans consists of physical components such as the brain, the sensory receptors, and the nervous system. The software consists of the mental processes and strategies used to store, interpret, access, and analyze information. The information-processing mechanisms of young children are elementary and immature. As children grow, as their nervous systems and brains develop, their information-processing strategies improve and become more sophisticated, like modern computers.

Humor and the appreciation of humor have also been associated with an individual’s level of cognitive development. A child whose mental structures and language acquisition have developed enough to enable the child to notice incongruities or deviations from the usual and expected can perceive humor in incongruous situations. To a two-year-old, calling a bird a cat may seem hilarious or making barking sounds and pretending to be a dog may provoke much laughter. A picture of a fish in a tree will amuse a three-year-old. Seven-year-olds who can understand the double meanings inherent in language will laugh at puns and “knock-knock” jokes and can create riddles. As children’s understanding of language ambiguities matures and becomes more sophisticated, they are able to appreciate more complex humor.

Sociocultural Factors

The Russian psychologist Lev Vygotsky (1896–1934) believed that cognition is sociocultural, that it is influenced by values and beliefs of cultures as well as by the specific tools that each culture uses for adaptation and problem solving. Children are born with simple mental processes such as attention, memory, perception, and sensation. These processes develop into what Vygotsky called higher mental functions, or more competent ways of using intellectual capabilities. The strategies and tools for thinking are taught to children by their culture and develop as young children interact and collaborate with capable adults or peers, who guide and model problem-solving techniques that encourage cognitive development. Vygotsky called the difference between children’s level of achievement when working independently and their potential development when guided by a competent adult the zone of proximal development.

For Vygotsky, language plays an important role in cognitive growth. Adults use language to transmit the culture’s ways of thinking to the child. The child uses language to plan and regulate activities and behavior and to solve problems. Language helps children organize thought and reach objectives. Younger children verbalize phrases and words aloud during this process, but older children and adults internalize speech that, although no longer uttered aloud, still organizes and guides thinking and action.

Disorders and Effects

The importance of experience on the cognitive development of children implies that when children live in intellectually impoverished environments, their cognitive development may be stunted or fail to reach its potential. Studies show the children whose parents play and interact with them in a variety of ways and provide stimulating materials to engage their interest and attention do better in school than children who lack this cognitive stimulation. Verbal interactions between parents and children, collaborative activities with competent peers, and guided activities with adults have been found to help children improve their thinking and planning abilities. Mary Ainsworth’s research on mother-infant attachment showed that mothers who interacted with their infants had securely attached children who, in turn, felt confident enough to explore their environment more independently than less securely attached infants. In this way, cognitive growth was affected by social functioning. Some longitudinal studies have found that securely attached children demonstrated more cognitive competence through childhood and adolescence than children who did not have secure attachments. Parental support and responsiveness encouraged cognitive growth over time.

The effects of the curriculum within programs and schools for children can maximize or discourage cognitive development. The Cognitively Oriented Curriculum, developed at the High/Scope Institute by David Weikart and his associates, focused on active learning. It was based on Piagetian principles and involved children in planning and other cognitively oriented activities. The games that children play can also affect their thinking and can be utilized in the curriculum. Research by Constance Kamii and Rheta DeVries has shown how the use of games and play-oriented activities can help children develop numerical thinking, language competency, and other cognitive abilities, while promoting autonomy or the ability to think independently and enhancing cooperative and social skills.

As an understanding of the negative effects of poverty and lack of enriching experiences increased during the 1950s and 1960s, initiatives such as Head Start and various other compensatory early childhood programs were established in the United States to reverse the effects of early cognitive deprivation. Initial studies on the effects of such programs were extremely encouraging, and gains in intelligence quotient (IQ) scores and cognitive performance were found to be significant. It was later discovered, however, that such gains could be lost if intellectual stimulation was not maintained. The need to continue to provide stimulating educational experiences was recognized. It was found that positive attitudes toward schooling and a sense of self-esteem also occur when compensatory education and enrichment programs are provided.

The increasing evidence of brain research concerning the importance of stimulating experiences to the developmental process during the first few years of life, as well as knowledge about the growth and weight of the brain in infancy, suggests the need to provide such experiences from a very early age. Prenatal experiences and their impact on cognitive and other areas of development are also being studied.

The concept of cognitive development as a highly active process that occurs in a series of stages has certain implications for the education and well-being of children. One implication is that children in a particular stage of development should not be hurried but should be allowed to develop and mature at their own pace. Hurrying children beyond their developmental capacity can cause mental and emotional damage. David Elkind uses the term “miseducation” to refer to the tendency to hurry and pressure children to perform activities and tasks for which they are not cognitively or physically ready. He believes that miseducation is an increasingly common problem in the United States.

Another implication of the active nature of cognitive development is that children should be given numerous opportunities to explore materials and the environment, and thus acquire knowledge for themselves. Materials, equipment, and knowledge to be discovered should be appropriate to the stage of the child and should be based on the child’s existing structures and schemes.

Perspective and Prospects

The cognitive and intellectual development of children was not studied seriously or scientifically until the late nineteenth century. G. Stanley Hall was the first person to develop an instrument—the questionnaire—to study the minds of children. The twentieth century saw the emergence of developmental theories such as the psychoanalytic theory of Sigmund Freud
and the psychosocial theory of Erik Erikson
. Behaviorism, which viewed children’s learning and development as passive and therefore controllable, dominated much of the earlier part of the century. John Watson proposed that children's minds were like blank tablets on which anything could be written. In other words, children’s development was thought to be shaped solely by their environment and by the people around them. This view had been held in the seventeenth century by the philosopher John Locke. Watson’s theory was extended by B. F. Skinner
, who evolved a learning theory based on the use of reinforcement and external stimuli to influence and control behavior. Albert Bandura’s theory of social cognition departed from the earlier passive learning theories of Watson and Skinner. He believed that individuals actively process information. Bandura also emphasized the role of observational learning, or learning by observing and mimicking others and thinking about outcomes, in the process of children’s development.

During the 1950s, a cognitive revolution occurred as the theory and research of Jean Piaget became known. Piaget was interested in how children think, in their “wrong” answers as indicators of their stage of cognitive development, and in their active construction of knowledge. He observed his own children’s early interactions and explorations. He also utilized the clinical method, in which he interviewed children of different ages to understand the nature of their hypotheses and problem-solving strategies. The questions in this method were flexible and depended on the responses given by the child.

Piaget’s theories were later criticized and were seen to underestimate children’s abilities. His assumption of the heterogeneity or universality of cognitive stages was also questioned. Critics charged that Piaget did not give enough credit to the role of cultural and social factors in cognitive development. The impact of culture and social interaction on the child’s thinking and use of strategies as culturally transmitted tools of thought was studied by Lev Vygotsky. In the last decades of the twentieth century, Vygotsky’s ideas aroused much interest. The difference in learning styles was also studied, and it was recognized that learning styles vary across cultures as well as from individual to individual.

Many neo-Piagetian theories attempted to integrate some Piagetian assumptions with information-processing approaches. These approaches examined cognitive processes such as memory and attention and demonstrated their influence on children’s cognitive development.

The influence of the environment and various activities cannot be overemphasized in its importance to cognitive development. As technologies continue to develop for use by children, ranging from toys to educational tools, it will be crucial to consider all aspects of development carefully. One example is recent research evaluating the impact on brain development of frequent video game and computer use by children. The research suggested that activities that encourage vision and movement skills, to the exclusion of other skills important to development, may be problematic. The concern is that some capacities may become overused, while others may not receive enough stimulation to encourage adequate development. More research is certainly needed to examine the potential impact of new technologies and exposure to diverse stimuli. Important lessons can be learned from history in an effort to guard against anything that impoverishes a child’s learning environment.

Bibliography

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