Developmental Psychology and Theories Developmental Psychologist and Theories

Piaget's cognitive theory of development

Jean Piaget developed the theory of cognitive development, which suggests there are four key stages through which children advance as their minds develop. The theory focuses largely on an understanding of the nature of knowledge and intelligence, and how they acquire and use it. Piaget lays the claim that cognitive development is key to human development and that language skills depend on cognitive development Fiore, 2011, p. 35.

This essay focuses on Piaget's theory of cognitive development and presents an explanation of the four stages of development in this theory.

The first stage of development is the sensorimotor stage, which happens from birth to about 24-month's age. During this period, the child begins to know the world around them and their sensations. It is in this period that as suggested by Rathus, 2011, p. 17(Piaget (1983, p. 152)

, assimilation is the process whereby children begin to see the environment and process new information using old or pre-existing information. For example when a child sucks their thumb for the first time and gain pleasure from this action, they may intentionally decide to do it again for the pleasure. Accommodation, on the other hand, occurs "when children alter pre-existing information in order to understand new information," Piaget and Inhelder (1973, p. 31)

, infants learn the existence of the objects in life and that they continue to exist even when they are out of view, a phenomenon referred to as object permanence. They also learn to, "differentiate objects from people and they often realize that their actions have consequences." They learn this through the processes of assimilation and accommodation. According to )

. A quintessential example of this is when a child may use different sounds to try to get the attention of the caregiver and from the reaction of the caregiver, they know which sound is more effective.

The second stage is the preoperational stage at the ages of 2 to 7 years where the child thinks symbolically and begins to use pictures and words to express themselves. At this point, Piaget & Inhelder, 1973, p. 38(

. At this stage,...

Role-playing is key in this stage and children mimic and imitate what their mother, father or nanny does in an attempt to learn language. One example of development in this stage is seen when a child uses a stick as a horse or an object as a toy car.
The concrete operational stage is the third stage and takes place between the ages of 7 to 11 years. In this stage, children begin to think logically about events that have taken place. During this period, they can understand the concept of conservation. This was tested in Piaget's experiment using thin and normal cups where children were asked which of the two holds the most amount of liquid. Children at this age are often able to know that the two cups hold the same amount of liquid. Piaget also found that children understand the concept of reversibility of actions Salkind, 2004, pp. 99-103.

This is where they are able to use inductive reasoning to more from specifics to general principles such as understanding that her dog is a poodle, and a poodle is a dog and that dogs are animals. Rathus (2008, p. 23)

argues that children at this stage "can focus on multiple parts of a problem at once," (p.23) Therefore, they can see objects from different points-of-view.

The last stage is the formal operational stage from the age of 12 years onwards. During this stage, the adolescent is able to think more abstractly, defined as "This type of reasoning can be done without thinking about actual objects," Brain & Mukherji, 2005, p. 77.

They also have the ability to use reason to solve problems and to think about moral, political, philosophical, and social constructs surrounding issues. Deductive reasoning emerges in this stage and they are able to "consider past experiences, present demands, and future consequences in attempting to maximize the success of his or her adaptation to the world," Salkind, 2004, p. 107()

Kohlberg's research on moral development

Lawrence Kohlberg presents six moral development stages that children must go through.…