1. Piagets Stage Theory of DevelopmentPiaget was among other things, a psychologist who was interested in cognitive development.After observation of many children, he posited that children progress through 4 stages andthat they all do so in the same order. These four stages are described below.The Sensorimotor Period (birth to 2 years)During this time, Piaget said that a childs cognitive system is limited to motor reflexes atbirth, but the child builds on these reflexes to develop more sophisicated procedures. Theylearn to generalize their activities to a wider range of situations and coordinate them intoincreasingly lengthy chains of behaviour.PreOperational Thought (2 to 6 or 7 years)At this age, according to Piaget, children acquire representational skills in the areas mentalimagery, and especially language. They are very self-oriented, and have an egocentric view;that is, preoperational chldren can use these representational skills only to view the worldfrom their own perspective.Concrete Operations (6/7 to 11/12)As opposed to Preoperational children, children in the concrete operations stage are able totake anothers point of view and take into account more than one perspective simultaneously.They can also represent transformations as well as static situations. Although they canunderstand concrete problems, Piaget would argue that they cannot yet perform on abstractproblems, and that they do not consider all of the logically possible outcomes.Formal Operations (11/12 to adult)Children who attain the formal operation stage are capable of thinking logically andabstractly. They can also reason theoretically. Piaget considered this the ultimate stage ofdevelopment, and stated that although the children would still have to revise their knowledgebase, their way of thinking was as powerful as it would get.It is now thought that not every child reaches the formal operation stage. Developmentalpsychologists also debate whether children do go through the stages in the way that Piagetpostulated. Whether Piaget was correct or not, however, it is safe to say that this theory ofcognitive development has had a tremendous influence on all modern developmentalpsychologists.Santrock, J. W. (1995). Children. Dubuque, IA: Brown & Benchmark.Siegler, R. (1991). Childrens Thinking. Englewood Cliffs, NJ: Prentice-Hall.
2. Vasta, R., Haith, M. M., & Miller, S. A. (1995). Child Psychology: The Modern Science.New York, NY: Wiley.Jean Piaget (1896-1980) was a biologist who originally studied molluscs (publishing twentyscientific papers on them by the time he was 21) but moved into the study of the developmentof childrens understanding, through observing them and talking and listening to them whilethey worked on exercises he set."Piagets work on childrens intellectual development owed much to his early studies of water snails"(Satterly, 1987:622)His view of how childrens minds work and develop has been enormously influential,particularly in educational theory. His particular insight was the role of maturation (simplygrowing up) in childrens increasing capacity to understand their world: they cannotundertake certain tasks until they are psychologically mature enough to do so. His researchhas spawned a great deal more, much of which has undermined the detail of his own, but likemany other original investigators, his importance comes from his overall vision.He proposed that childrens thinking does not develop entirely smoothly: instead, there arecertain points at which it "takes off" and moves into completely new areas and capabilities.He saw these transitions as taking place at about 18 months, 7 years and 11 or 12 years. Thishas been taken to mean that before these ages children are not capable (no matter how bright)of understanding things in certain ways, and has been used as the basis for scheduling theschool curriculum. Whether or not should be the case is a different matter.MorePiagets Key IdeasAdaptation What it says: adapting to the world through assimilation and accommodationAssimilation The process by which a person takes material into their mind from theenvironment, which may mean changing the evidence of their senses to make itfit.Accommodation The difference made to ones mind or concepts by the process of assimilation.Note that assimilation and accommodation go together: you cant have onewithout the other.Classification The ability to group objects together on the basis of common features.Class Inclusion The understanding, more advanced than simple classification, that some classesor sets of objects are also sub-sets of a larger class. (E.g. there is a class ofobjects called dogs. There is also a class called animals. But all dogs are also
3. animals, so the class of animals includes that of dogs)Conservation The realisation that objects or sets of objects stay the same even when they arechanged about or made to look different.Decentration The ability to move away from one system of classification to another oneas appropriate.Egocentrism The belief that you are the centre of the universe and everything revolvesaround you: the corresponding inability to see the world as someone else doesand adapt to it. Not moral "selfishness", just an early stage of psychologicaldevelopment.Operation The process of working something out in your head. Young children (in thesensorimotor and pre-operational stages) have to act, and try things out in thereal world, to work things out (like count on fingers): older children and adultscan do more in their heads.Schema (orscheme)The representation in the mind of a set of perceptions, ideas, and/or actions,which go together.Stage A period in a childs development in which he or she is capable of understandingsome things but not othersStages of Cognitive DevelopmentStage Characterised bySensori-motor(Birth-2 yrs)Differentiates self from objectsRecognises self as agent of action and begins to act intentionally: e.g. pulls astring to set mobile in motion or shakes a rattle to make a noiseAchieves object permanence: realises that things continue to exist even when nolonger present to the sense (pace Bishop Berkeley)Pre-operational(2-7 years)Learns to use language and to represent objects by images and wordsThinking is still egocentric: has difficulty taking the viewpoint of othersClassifies objects by a single feature: e.g. groups together all the red blocksregardless of shape or all the square blocks regardless of colourConcrete operational Can think logically about objects and events
4. (7-11 years) Achieves conservation of number (age 6), mass (age 7), and weight (age 9)Classifies objects according to several features and can order them in seriesalong a single dimension such as size.Formal operational(11 years and up)Can think logically about abstract propositions and test hypothesessystemticallyBecomes concerned with the hypothetical, the future, and ideological problemsThe accumulating evidence is that this scheme is too rigid: many children manage concreteoperations earlier than he thought, and some people never attain formal operations (or at leastare not called upon to use them).Piagets approach is central to the school of cognitive theory known as "cognitiveconstructivism": other scholars, known as "social constructivists", such as Vygotsky andBruner, have laid more emphasis on the part played by language and other people in enablingchildren to learn.See here for Howard Gardners re-evaluation of Piaget: still a giant, but wrong in practicallyevery detail.And the combination of neuroscience and evolutionary psychology is beginning to suggestthat the overall developmental model is based on dubious premises. (Its too early to giveauthoritative references for this angle.)Jean Piagets BackgroundJean Piaget was born in Switzerland in 1896. After receiving his doctoral degree at age 22,Piaget formally began a career that would have a profound impact on both psychology andeducation. After working with Alfred Binet, Piaget developed an interest in the intellectualdevelopment of children. Based upon his observations, he concluded that children were notless intelligent than adults, they simply think differently. Albert Einstein called Piagetsdiscovery "so simple only a genius could have thought of it."Piagets stage theory describes the cognitive development of children. Cognitive developmentinvolves changes in cognitive process and abilities. In Piagets view, early cognitivedevelopment involves processes based upon actions and later progresses into changes inmental operations.Key ConceptsSchemas - A schema describes both the mental and physical actions involved inunderstanding and knowing. Schemas are categories of knowledge that help us to interpretand understand the world.In Piagets view, a schema includes both a category of knowledge and the process ofobtaining that knowledge. As experiences happen, this new information is used to modify,add to, or change previously existing schemas.
5. For example, a child may have a schema about a type of animal, such as a dog. If the childssole experience has been with small dogs, a child might believe that all dogs are small, furry,and have four legs. Suppose then that the child encounters a very large dog. The child willtake in this new information, modifying the previously existing schema to include this newinformation.Assimilation - The process of taking in new information into our previously existingschemas is known as assimilation. The process is somewhat subjective, because we tend tomodify experience or information somewhat to fit in with our preexisting beliefs. In theexample above, seeing a dog and labeling it "dog" is an example of assimilating the animalinto the childs dog schema.Accommodation - Another part of adaptation involves changing or altering our existingschemas in light of new information, a process known as accommodation. Accommodationinvolves altering existing schemas, or ideas, as a result of new information or newexperiences. New schemas may also be developed during this process.Equilibration - Piaget believed that all children try to strike a balance between assimilationand accommodation, which is achieved through a mechanism Piaget called equilibration. Aschildren progress through the stages of cognitive development, it is important to maintain abalance between applying previous knowledge (assimilation) and changing behavior toaccount for new knowledge (accommodation). Equilibration helps explain how children areable to move from one stage of thought into the next.More About Piagets Stages of Cognitive DevelopmentThe Sensorimotor StageThe Preoperational StageThe Concrete Operational StageThe Formal Operational StageSupport and Criticism of PiagetDid You Know?By visiting the rest of the Psychology site you can find a wealth of free psychology articlesand resources, which include:Blog and Weekly Feature StoriesFree Psychology Newsletter and E-CoursesDiscussion BoardsPsychology Tests and QuizzesReferencesSantrock, John W. (2008). A topical approach to life-span development (4 ed.). New York City: McGraw-Hill.Piaget, J. (1977). Gruber, H.E.; Voneche, J.J. eds. The essential Piaget. New York: Basic Books.Piaget, J. (1983). Piagets theory. In P. Mussen (ed). Handbook of Child Psychology. 4th edition. Vol. 1. New York: Wiley.
6. More About Cognitive DevelopmentBiography of Jean PiagetSensorimotor Stage of Cognitive DevelopmentPreoperational Stage of Cognitive DevelopmentMore About Cognitive DevelopmentConcrete Operational Stage of Cognitive DevelopmentFormal Operational Stage of Cognitive DevelopmentCognitive Development in Early ChildhoodSuggested ReadingQuiz - Piagets Stages of Cognitive DevelopmentSupport and Criticism of Piagets Stage TheoryKohlbergs Theory of Moral Development