During the ages 2-7 years children enter into the pre-operational stage where they move on from simple problem solving and learn to use mental symbols to represent their experiences and satisfy their goals. The emergence of simple language provides additional flexibility in the field of intelligence by enabling the child to plan, mentally represent objects that aren’t present and consequently solve more complex tasks.
From aged 7 onwards children then enter the stage of concrete operations where they learn to reach logical conclusions by using internal mental processes, as opposed to conclusions based largely on external appearances.
The final stage defined in Piaget’s theory of intelligence is the stage of formal operations. This stage generally occurs around the age of 12 and involves the early adolescent development of reasoning skills on the basis of hypotheses, ideas.
According to Piaget, the ability for children to construct these intellectual schemes is based on a system of organisation and adaptation. Children use organisation to combine their existing mental schemes into more complex structures. He suggested that the purpose of this organisation is to promote an adjustment to the demands of the environment, otherwise known as adaptation. He believed this process of adaptation to the environment occurs through two processes, assimilation and accommodation. Children will try to understand new experiences and events by assimilating them into their existing and more familiar schemata. Obviously these new experiences will not appropriately fit their existing schemata, and consequently the child is required to adapt their mental schemes accordingly. This process is known as accommodation. Piaget believed that the processes of assimilation and accommodation work together to facilitate this staged cognitive development, and he describes this growth as an invariant developmental sequence. This universal process assumes that all children progress through this sequence of fixed stages, with each stage building on the previous stage.
In contrast to Piaget, a theorist named Vygotsky proposed the Socio-Cultural perspective of development. His theory focused on culture as a predominant factor in cognitive development. He believed that children are born with basic attention sensory and memory functions that are built upon by cultural influences and their environment, as opposed to a series of inbuilt biological stages to form higher more complex mental functions (Vygotsky, 1930-1978). Although he did not dispute the fact that children are active and curious explorers, he argued that a child’s social influences provide a far more important contribution to cognitive development than simply a staged process of self initiated discovery.
He felt that children learn by internalising verbal instructions from a tutor or role model until they are capable of working and thinking independently. Vygotsky used the term the ‘zone of proximal development’ to describe a range of tasks that are too complex for a child to master unsupervised, but can be mastered with the help and encouragement of a more skilled person. The process of carefully building on these newly found skills to increase the understanding of the child is known as scaffolding. Vygotsky’s theory has important implications for child development as it relies heavily on the contact and interaction of peers and role models to facilitate the development of cognitive skills. Further studies (Bjorkland & Reubens, 1997) supported Vygotsky by confirming that the use of scaffolding enables children to become more competent at solving problems.
Both Piaget and Vygotsky’s studies have used language as a measure of cognitive development. According to Vygotsky, language provides the main medium for adults to transfer instructions and ideas to the child. He also described language as a ‘tool of intelligence’, a method of building upon and adjusting existing skills in order to develop new ideas and concepts. This method of scaffolding eventually provides the child with the ability to think and reason independently.
In contrast Piaget described language merely as a reflection of a child’s mental activity, although he still assumed that the extent of language expressed by the child, represented their level cognitive maturity. He defined the term ‘egocentric speech’ to describe the running commentary type talk used by young children when performing a task. He felt that because the talk wasn’t directed at anyone in particular and appeared to have no purpose it was of little value to actually facilitating cognitive development. He did acknowledge that speech becomes more social and less egocentric towards the end of the preoperational stage, however he assumed that this was largely due to the fact that the child was becoming able to observe the perception of others around them.
He therefore assumed that cognitive development promoted language, because of the shift from egocentric speech to communicative speech. Consistent with Piaget’s findings are numerous studies that have found that pre-linguistic children can form concepts long before they acquire the ability to verbally describe them (Younger 1990; 1993). Piaget also highlighted the fact that the use of imaginary play also demonstrates that children are able to use mental representations to symbolize other objects prior to language development. For example a child may use a washing-up bottle to symbolise a train.
Vygotsky’s observations of children however found that children were more likely to talk to themselves if they were trying to solve more complex problems and tasks, which would indicate that language plays an active role in facilitating problem solving. In contrast to Piaget, Vygotsky proposed that language was an organisation tool that actually promoted cognitive development. He believed that children’s private, or as Piaget referred to as ‘egocentric speech’ does not actually disappear, but it internalises and becomes the silent verbal thought that we use during our everyday cognitive processes.
Further research into the important link between language and cognitive development favoured Vygotsky’s theory over Piagets. Observations (Berk, 1992) also discovered that children’s intellectual ability often improves with the increased use of private speech. More intelligent children have also been found to rely more heavily on private speech as opposed to it being viewed as a sign of cognitive immaturity and egocentricism (Berk1992; Kohlberg, Yaeger and Hjertholm, 1968) It has also been found that the brighter the child the earlier the internalisation of private speech (Berk and Landau, 1993).
Piaget was fascinated by children’s play as he felt it provided the initial view of their development of cognitive schemes. He identified preoperational two to four year old children as pre-conceptual and egocentric because of their primitive reasoning ability and tendency to view the world from their point of view. He noted from listening to their conversations that they often displayed transductive reasoning, and would make judgements based on focusing on single appearance based aspects of a situation (Sedlack & Kurtz, 1981). Piaget therefore concluded that preoperational children were unable to master conservation tasks (Piaget, 1970b).
An interesting study however, showed that pre-operational children are actually capable of being taught conservation (Brainerd, 1974; Gelman, 1969; Hendler and Weisberg, 1992). According to Field (1981) children are able to use their new skills to solve other conservation problems and she concluded that this was based on the ability of the child to recognise identities. These findings tend to support Vygotsky’s view that language promotes cognitive development and reasoning.
The development of language at around the age of four appears to account for the dramatic improvement in the child’s ability to recall information and use it to reason and solve more difficult tasks. This sudden increase in ability also coincides with the large increase in vocabulary. Language acquisition and the formation of memory related structures provide the child with the ability to encode material verbally as opposed to visual representation (Fivush et al., 1987). The findings of Vygotsky show that the use of private speech clearly plays a role in the child encoding information in order to remember and formulate plans. A linguist named Noam Chomsky provided a valuable contribution to the insight into cognitive and language development in 1952. He proposed that humans have an innate capability to process language and exposure to speech in childhood triggers this capability. He concluded this because speed of vocabulary development in the child could not be accounted for by simple imitation of a parent or older child.
The findings of both Piaget, Vygotsky and other theorists shows that cognitive development occurs as a result of a child’s adaptation and interaction with their environment and clearly language plays an important role in learning. Biological maturation certainly influences cognitive development but whether or not language actually promotes cognitive development or vice versa remains debatable. Vygotsky proved that a child’s environment obviously plays a crucial role in development. He emphasised that language and the culture in which one is raised initiates development (Vygotsky, 1987).
To conclude, I would suggest that both biological and sociological factors interact during cognitive development. A child can not progress from one Piagetian stage until his or her brain has matured sufficiently to enable them to be competent at solving problems associated with the next stage. And certainly through interaction with adults, children are introduced to a wide range of new linguistic skills to enable them to form new concepts, reason and solve complex problems. This is obviously vitally important around the period of four years old where there is an apparent boom or sensitive period for language acquisition.
