Life-span development is the scientific study that seeks to understand the ways in which all people change and how they do not change from conception to death. Until recently developmental psychology focused mainly on childhood and adolescence but, as a greater understanding of adult “crises” arose, developmental psychology has “enlarged to encompass the entire lifespan.” (Bee & Boyd, 2003). One of the most influential theorists in the realm of development was Swiss born psychologist Jean Piaget. Piaget specifically studied the cognitive development of children and adolescents. Unfortunately Piaget failed to recognise that development continued past adolescence and right the way through an individual’s entire life. It is because of this omission that many criticise and question the validity of Piaget’s theories.
Classical Piagetian theory is a theory of cognitive development centred on adaptation, accommodation and assimilation. Unlike Locke’s proposal of the “tabula rasa”, Piaget believed that a child’s mind is not a blank slate. “On the contrary, the child has a host of ideas about the physical and natural world, but these ideas differ from those of adults.” (Santrock, 2002). Piaget used his theory on adaptation, the ideas that children took learned knowledge and applied it to a new situation and that they modified existing schemas to include or exclude this new information, to formulate his four infamous stages of cognitive development.
He proposed that all children progress through these four age related stages in their cognitive development and that progress through these stages is in a fixed order. “Each successive stage builds on, and is derivative of, the previous one when more adaptive cognitive abilities are added to what has previously been achieved. Transition from one stage to the next entails a fundamental reorganisation of how the child interprets the world and while the order of stages does not change some children reach a particular stage earlier, or later, than others.” (Mussen, Conger, Kagan & Huston, 1984).
Piaget’s four proposed stages of cognitive development begin with the sensori-motor period from birth to 2 years old. Between the ages of 2 and six children are thought to be in the pre-operational period. The third period children pass through is the concrete operational stage from 6 to 12 years old and finally the formal operations period form 12 year old through to adulthood. Piaget proposed that in the primary stage, the sensori-motor period, children combine motor tasks with co-ordination of new information to develop a way of learning and thinking.
It is also said that within this stage the infant learns the notion of object permanence. In the pre-operational stage the child learns to focus on symbolism, an ability to think in ideas, and use words to express those ideas. Piaget felt that children in this second stage were limited by egocentrism, the notion that they could only see things from their own point of view. Piaget used his experiment with the “mountains and a doll” to illustrate this point.
“Piaget also observed that at this stage children are incapable of understanding conservation so that they do not understand the concept that the form may change but that the quantity may stay the same.” (Mussen et al, 1984). In the third stage, the period of concrete operations, the child can think logically and quantitatively but is unable to deal with complex operations or abstract thinking. Children can now grasp the skill of conservation and can now engage in mental operations that are both flexible and reversible. In the final stage, the formal operations stage, Piaget theorised that the child can now begin to reason as they are gathering intellectual capabilities that are allowing them to manipulate ideas about hypothetical situations.
Piaget’s theory of cognitive development has come under many criticisms from different theorists. We must take into account that Piaget wrote this theory in 1930 when Psychology as a discipline was only taking off. It would be absurd to presume that unrefined theories from 80 years ago could hold to be totally true in the present day, taking into account the many technological and social advances that have been made. Many theorists have further researched the concepts that underlie each of Piaget’s four stages. There is evidence to support his concepts but a considerable amount of evidence that he may have underestimated children’s mental capacity. For example Bower (1982) showed that object permanence could be seen in children as young as a few months old.
Bower monitored children’s heart rates to measure changes which reflected surprise. This method of monitoring heart rates would not have been accessible to Piaget in the 1930’s. Baillargeon & DeVos (1991) preformed experiments which also yielded evidence that; “young children are aware of the continued existence of objects even when they have been out of view. The results from Bower (1982) and from Baillargeon & DeVos (1991) indicate that children have some understanding of object permanence earlier than Piaget suggested.” (Smith, Cowie & Blades, 4th Edn). Piaget also claimed that imitation occurs only toward the end of the sensori-motor stage.
“However, Meltzoff & Moore (1994) showed that six week old infants could imitate a behaviour a day after they had seen the original behaviour.” (Smith, Cowie & Blades, 4th Edn). All these theorists have provided evidence of mental representations in children at a much earlier age than Piaget had proposed. A reason put forward to explain why Piaget may have underestimated infant cognition was that he may have been limited by direct observation of his own three infants. Also technological advance such as fMRI (functional magnetic resonance imaging) have provided present day theorists with new methods to study cognition that were not available to Piaget. fMRI has given us empirical evidence of mental combinations and memories in infants earlier than Piaget predicted. “So although modern research finds that Piaget underestimated infant cognition, his basic concepts still inspire researchers.” (Berger, 2005).
Many of Piaget’s research methods in the pre-operational stage of cognitive development have also come under attack. First to come under criticism were his methods used to test conservation. These tests focus mainly on the child’s words and not his actions. Researchers found that “children as young as 3 years old can distinguish appearance from reality if the test is non-verbal.” (Berger, 2005). Donaldson challenged his methods of testing conservation by introducing a “naughty teddy” into her experiment with reorganised rows of sweets or checkers. She found that children could understand the concept of conservation at a much younger age than Piaget had claimed.
Donaldson explained that because it was the “naughty teddy” rather than the experimenter who had muddled up the display a child might have fewer expectations that a deliberate action had occurred and so they had no reason to believe that a real change had occurred. Hence because this experiment now made “social sense” to the child they are more likely to provide the correct answer. This idea of the importance of social influences on cognitive development was introduced by the Russian psychologist Vygotsky. It has been said that Piaget limited his developmental theories to cognition omitting any kind of social factors which today have been proved to contribute greatly to development. Many theorists believed that Piaget “designed his experiments to reveal what young children seemed not to understand, rather than identify what they could understand.” (Berger, 2005).
Piaget’s “three mountain test” used to demonstrate the egocentric viewpoint of the pre-operational child has proved to be another bearer of great criticisms. The notion of mountains is alien to non Swiss or children unfamiliar with mountains. Donaldson replaced the mountains with her “hiding from the policeman” experiment and found 90% of children completed the task successfully. From these results it appears that children at this stage can decentre from being egocentric earlier than Piaget thought if the tasks are presented in a relevant context to the child. We can see from the “three mountains” test that
Piaget’s research can be criticised as being culturally specific and can hence have no standing as being a standardised cross cultural theory. For example; “different societies value and reward different skills so that when people from underdeveloped societies are tested they appear to have less success in solving Piagets concrete and formal operational tasks, but these differences disappear when culturally relevant tasks are applied.” (Passer & Smith, 2001).