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How the mind develops

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In reading books about Piaget’s theory of stages of development, one often gets the impression that the formal operations stage is the final stage of thinking, and that everyone ends up reaching it. But that is not the case. Piaget himself came to this conclusion when he observed in the early 1970s that a significant percentage of adults could not solve certain problems specific to the formal operations stage, such as the pendulum problem discussed elsewhere on this page.

As for the idea that no one can go further than the formal operations stage, nothing could be less certain. For Piaget, there were no limits to human development. Hence he even posited “post-formal operations” stages or “operations to the nth power” stages that might be reached by professional mathematicians or specialists in other fields involving a high degree of abstraction.

A similar succession of stages is observed in postural and motor development: babies learn first how to hold their heads up, then how to sit upright, then how to stand, and finally how to walk.

In 1946, Arnold Gesell showed that this succession proceeded from the top of the body downward (cephalo-caudally) and, for each arm or leg, from the segments closest to the trunk outward (proximo-distally).

Gesell also pointed out that this phenomenon was progressive, because each stage involved an increase in the control of muscle tonus and in the co-ordination of movements, both of which were made possible by the maturation of the nervous system.

“It is through action that the newborn constructs its body schema. When its hand touches its foot, the two sensations, one in the hand and the other in the foot, turn inward onto its own body, whereas if the infant touches its bib, or its mother’s breast, then the sensation in its hand opens onto the outside world. It takes the infant 18 months to two years to realize that it is separate from the world surrounding it, that it will be alone in its skin until the day it dies.”

- Henri Laborit,
La légende des comportements, p.93


Jean Piaget’s studies on cognitive development laid the foundations for the entire discipline of developmental psychology. Though some of his data have been criticized since, he remains the pioneer of empirical experimentation with children, and his research results have influenced teaching practices considerably.

Piaget used the term “constructivism” to describe his approach, because he believed that the acquisition of knowledge is a lifelong process of continuous self-construction. He also spoke of “interactionism” to stress the constant interaction between heredity and environment in developmental processes. All of this seems obvious to us today. But for a large part of Piaget’s career, his approach was taken less seriously than approaches such as Arnold Gesell’s, which basically emphasized genetic maturation as the source of child development, or, conversely, purely behaviourist approaches such as B.F. Skinner’s.

To Piaget, knowledge is nothing more and nothing less than a biological function that takes the form of a distinctive cognitive structure in every individual. This structure emerges from the individual’s actions and develops both by assimilating new information into schemas that are already part of it and by accommodating (adapting) to new information that does not fit into it in its current form.

In popular culture, Piaget is known mainly for his model of stages of development, but it is this concept of the cognitive structure that is at the heart of Piagetian theory. The four major stages of development that he described were for him nothing more than guideposts for following the process of cognitive development in children. Moreover, in Piaget’s view, other major stages beyond these four were possible, and every stage could be divided into substages.

In the first stage following birth, the sensorimotor stage, thought develops through action. This stage is divided into several substages. Substage 1— innate reflexes—occurs during the first month of life, and involves reflex actions such as sucking, crying, coughing, wriggling, urinating, and defecating. Substage 2—primary circular reactions—lasts until about 4 months of age. In substage 2, babies tirelessly repeat actions that give them pleasure, such as sucking their thumbs. Next comes the period when babies discover that they are separate from the outside world. They begin to repeat actions that that gave them some kind of satisfaction when they first performed them at random. Around 1 year of age, children become aware of cause-and-effect relationships and the permanence of objects—if an object is removed from their field of vision, they will start looking for it immediately. Between 1 and 2 years, children begin actively seeking novelty through experimentation. For example, a child might bang on various objects with his spoon to try to get different sounds out of them. As they approach age 2, children clearly develop mental representations that let them, for example, imitate a gesture that they see someone else make, draw simple empirical conclusions, pretend that a given object is really something else, and so on.

Link : L'enfant de 0 à 3 ans

By presenting certain concrete problems and questioning children about them, Piaget was able to determine whether a given skill was attained within a given stage of development. For example, in the problem illustrated here, he might pour the liquid from the low, wide container on the left into the tall, narrow one on the right, then ask the child whether the amount of liquid in the second container was the same or different. A child in the preoperational stage (age 2 to about 6 or 7) would say that there was more liquid in the second container, because the level of the liquid was higher. But a child in the concrete operations stage (beginning around 6 or 7) would know that, despite appearances, the same volume of liquid had been conserved.

Link : l'enfant de 3-6 ans

The capacity for conservation—the general ability that lets the child see that a volume remains the same despite a change in appearance—develops for lengths and numbers at age 6 or 7 as well. For example, in the problem illustrated below, the child will no longer say that there are more blue dots in the top row on the right simply because they have been spread out.

Conservation of substance generally develops a bit later, around age 7 or 8. Suppose, for example, that you show a child three identical balls of clay, then leave the first one intact, flatten the second one into a pancake, and divide the third one up into smaller balls. If you then ask her whether the second ball still contains “the same thing” (the same amount) as the first, and she is less than 7 or 8 years old, she will answer that it contains less, because it is flatter. But if she is 7 or 8 or older, she will not be fooled by appearances.

Conservation of area is the last kind to be mastered—often not until age 9 or 10. At that age, children will know, for example, that even though the four yellow squares shown below seem to occupy more area when they are grouped together than when they are spread apart, in reality they do not.

Link : L'enfant de 6-12 ans

Lastly, here is a problem that children who are still at the concrete operations stage cannot solve, but that adolescents (and adults) at the formal operations stage can, with a little time and effort, to be sure. Say you have a deck of cards that supposedly follows this rule: if there is a vowel on one side of a card, then there has to be an even number on the other. Subjects are told that each card has a letter on one side and a number on the other. Which of the four cards shown here do you have to turn over before you can tell whether they follow this rule? (The answer appears below, but try to figure it out for yourself before you peek!)

The answer is: the E card and the 7 card. For the rule to be true, the E card absolutely must have an even number on the other side, so you must turn it over to check. And since 7 is an odd number, you have to turn the 7 card over to make sure there is no vowel on the other side, because that would break the rule. Since the rule does not say anything about what should be on the other side of a card with a consonant, such as K, and does not say that there has to be a vowel on the other side of a card with an even number, such as 4, you do not need to check those cards!

Contrary to what educators had long believed before Piaget came along, children are not just empty “containers” to be filled up with knowledge. On the contrary, they truly act as “lone scientists”, constantly creating and testing their own theories about the world.

This is especially true of adolescents who have reached the formal operations stage. For example, if you ask a teen to find out what makes a pendulum swing faster or slower, he or she will probably start by testing a long string with a light weight at the end, then the same length of string with a heavier weight, then a shorter string with the lighter weight, and finally the shorter string with the heavier weight. From these observations, which actually constitute a simple scientific experiment, the teen will deduce that the shorter the string, the faster the pendulum swings, and that the weight at the end of the string makes no difference.

To Piaget, science, just like the organization of an individual’s knowledge, is a tool for adapting more effectively to the environment. Just like scientific theories, individuals’ cognitive structures are the product of active researchers who modify their way of thinking constantly to adjust it to the constraints of experience.



Children's needs: Dr. Stanley Greenspan The Needs of Children Emotional Origins Of Intelligence The Importance of One-on-One Time
Floor Time: The Developmental, Individual Difference, Relationship-based Model for Intervention Livres pour les parents : « L'esprit qui apprend : affectivité et intelligence », Stanley Greenspan, Paris, Odile Jacob, 1998 Nonconceptual Mental Content Le déterminisme biologique et social du concept d'intelligence LA SIGNIFICATION ÉVOLUTIVE DE L'INTELLIGENCE HUMAINE
Original modules
Experiment Module: Neuropsychologists Show How Emotions Affect Cognition and Decisionmaking Neuropsychologists Show How Emotions Affect Cognition and Decisionmaking
Tool Module: Resilience   Resilience

In experiments conducted with pregnant women and their fetuses during the final weeks of pregnancy, the mothers were asked first to keep silent for three minutes and then to sing a song, while their babies were filmed in the womb by means of ultrasound. When the mothers began to sing, all the babies instantly began to move, and their heartbeats accelerated. But when numerous films were compared, it was found that the babies’ reactions varied widely, ranging from very lively to quite subdued.

Since any given song inevitably has a particular emotional overtone, it would seem that a baby’s interactions with its mother’s emotions begin to shape its temperament even while it is still in the womb.

Similarly, when a mother lets herself form certain mental images, they too can have somatic manifestations that affect the fetus. For example, it is known that some small molecules generated by stress pass through the filter of the placenta and influence the fetus’s subsequent development.


Many criticisms have been levelled at Piaget and his concept of child development. Some authors, such as Vygotsky, have focused on the social environment as the main engine of cognitive development, while others have drawn attention to the importance of emotions for the sound development of the human mind.

Stanley Greenspan falls in the latter group. On the basis of his experience in working with autistic children, Greenspan believes that intelligence is structured by affective (emotional) experience. Contrary to the traditional concept of development, which separates emotion from reason, Greenspan believes that emotions play a central role in learning and in the development of our intellectual faculties (for one example of how, follow the Experiment Module link to the left).

Thus the essence of Greenspan’s vision of development runs counter to Piaget’s and gives more weight than even Freud did to the role of our early emotional experiences in the development of our intellectual and social faculties.

So what does each child need in order to develop successfully, according to Greenspan? First of all, a safe, secure environment in which he or she can develop a relationship with a stable, protective adult. The rich, continuous interactions that begin with such an adult at the very start of life can them become increasingly subtle and complex. Children can then experiment, find solutions, take risks, fail, and try something else, all within limits and structures clearly established by the adults in their lives.

The mode of intervention that Greenspan recommends for working with children is called “floor time”: time spent on the floor, following children in their play. The main idea is to take whatever activity the child initiates as the point of departure, then try to introduce an affective interaction into this activity.

For example, if a father and his daughter start taking turns lining up blocks in a row on the floor, the child will understand the routine and wait for her father to put his block down before she puts hers. If the father then puts down two blocks in a row, or puts his block down out of line, his daughter will want to correct the error. The father has thus created an opportunity to, in Greenspan’s terms, “open and close a circle of communication”.

In such situations, far from posing an obstacle to clear, logical thinking, emotions constitute the “glue” that binds all aspects of intellectual and social development together. In fact, abstract concepts are often classifications based on emotional experiences in the real world.

Consider the mathematical concept of quantity, for example, which children derive from two kinds of emotional experiences. The first is the feeling of “a lot ”that children learn when they receive more things than they were expecting. The second is the feeling of “a few ” that they get when they receive fewer things than they would like. Children thus assimilate the concept of quantity on the basis of expectations with a strong affective component. Later, children can systematize these experiences with numbers, so that 10 becomes “a lot ” and 2 becomes “a few”. Thus children’s understanding of supposedly cold, logical mathematics is actually anchored in the affective experiences through which they first learned concepts of numbers.

According to Greenspan, this same principle extends to more abstract concepts such as justice. Tomorrow’s judges will have to study the laws by which society codifies this concept, but their intimate knowledge of what justice means will come from their personal lives and their own experiences of having been treated fairly or unfairly.

In Greenspan’s model, it is therefore essential for each child to develop the feeling of his or her individuality. It is through this feeling of being themselves and not someone else that children become capable of desiring and of having intentions. Every effort should therefore be made to encourage whatever helps children build this feeling of having their own personalities.

Psychologist Erik Erikson’s contribution to developmental psychology also emphasizes the sound development of the feeling of personal identity. Unlike Freud, who believes that most of our personality structure has been determined by age 5, or Piaget, who believes that the kind of reasoning that we master in adolescence (formal operations) is fairly close to the kind that we use for the rest of our lives, Erikson says that our personalities continue to develop throughout our lives. He distinguishes eight stages of psychological development, in each of which a particular psychological crisis predominates, triggered by a predominant type of interaction with the social environment.

Link : Erik Erikson : Socioemotional Development Research : Erik Erikson


Maternal care Mother Love Makes Rats Smarter Human Contact and Affection are Powerful Stress Reducers Can Adverse Neonatal Experiences Alter Brain Development and Subsequent Behavior?
Brain Work-outs Child Abuse and the Brain Parental Care and The Brain Inside the teenage brain
Child care providers : how brains develop in young children ENCYCLOPEDIE SUR LE DEVELOPPEMENT DES JEUNES ENFANTS
Michael Meaney
Original modules
Experiment Module: The Effect of an Enriched Environment on Memory The Effect of an Enriched Environment on Memory

The quality of resilience has been observed in some children who were abused or traumatized by various atrocities committed in the course of history. These resilient children developed normally afterward and in some cases even seemed better equipped to face adversity than most people are. One theory is that traumatized children who show resilience acquired a “primitive confidence” between birth and 12 months of age that subsequently let them maintain the hope of meeting someone who would help them to resume their development.

Resilience is a complex phenomenon in which developmental biological forces join with the social context to create a representation of the self that lets the individual forge a meaningful personal history.

Because the brain’s various systems do not all become mature at the same time, the critical periods for various brain functions differ. The critical period for each of these functions represents a vulnerable interval when the individual is highly sensitive to influences from the environment, including traumatic experiences. Traumas suffered in childhood can therefore permanently affect the way a person’s mind is organized.

Link : Violence and Childhood: How Persisting Fear Can Alter the Developing Child's Brain Link : Childhood Trauma, the Neurobiology of Adaptation and Use- dependent Development of the Brain: How States become Traits Tool : La résilience

During the first years of life, the influence of the environment on development is crucial. The most pronounced changes induced by the environment occur during windows of time called critical periods.

All critical periods have certain basic properties in common. First, they all involve a time window during which a given behaviour is more sensitive to specific environmental influences. These influences are even necessary for the normal development of the behaviour in question. Once the critical period is over, the behaviour is no longer significantly affected by the presence or absence of these environmental stimuli. And, as a corollary, if the individual is not exposed to the appropriate stimuli during the critical period, it is difficult if not impossible to compensate for this lack later on.

Many critical periods have been detected in the development of behaviours in a number of species. But the existence of a critical period does not necessarily mean that a given experience will subsequently have no effects on brain development. It simply means that certain major restructuring will then be more difficult, if not impossible, because some irreversible changes will have taken place at the synaptic level.

For instance, people who are deprived of the use of one of their senses during a certain critical period at the start of their lives may still have permanent gaps in this sense even if they reacquire the use of it later on. There have been cases where people who were born blinded by cataracts had them removed and their sight restored between ages 10 and 20. Subsequently, they were able to perceive colours, but would always have great difficulty in distinguishing shapes.

Experience: Effets de la privation visuelle durant la période critique du development de la vision


Also, if children are emotionally deprived or mistreated during certain periods of their development, it can have an irreversible impact on their emotional equilibrium when they become adults. Many authorities regard the first three years of life as a critical period for the neural pathways involved in forming social and emotional relationships. If children are exposed to repeated negative experiences during this period, their social and emotional equilibrium may remain fragile for the rest of their lives, and they may be subject to episodes of anxiety or depression.

History : L’isolation et ses effets dévastateurs sur le comportement social

Many studies have shown that such mood disorders are accompanied by hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. This axis is directly involved in controlling stress: the levels of cortisol in the blood, like those of CRH in the cerebrospinal fluid, are very high in severely depressed patients.

Experiments have shown that in rats, sensory experience early in development regulates expression of the genes that encode the receptors for glucocorticoids. Young rats that receive attentive maternal care develop more receptors of this type in their hippocampus and fewer receptors for CRH in their hypothalamus. As a result, when these rats become adults, they tend to display relatively little anxiety.

The explanation is that when cortisol activates the receptors for glucocorticoids in the hippocampus, there is a negative feedback effect on the activity of the HPA axis. In people who have experienced affective deficits during the critical first three years of their lives, this control loop is disrupted, which explains the hyperfunctioning of this neural/endocrinal axis and the associated chronic stress.

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