In: Psychology
Jean Piaget, believed that every individual goes through four stages in life that shapes their cognitive development. The four stages being; sensorimotor stage (0-2 years), preoperational stage (2-7 years), concrete operational stage (7-11 years) and finally the formal operational stage (11-adulthood).
An individual at birth, in the first stage of cognitive development only relies on his reflexes. It is during the course of time that he learns to imitate actions. It's during this stage that he assimilates and accommodates new information which reflects in his thinking process. It is in the second stage of development, preoperational stage, that a child learns to use language, symbol and gestures for cognitive development. At concrete operational stage an individual is egocentric, It does not mean that he/she is selfish but they focus only on their feelings and thoughts and feel that everybody else around them feel and think the same way. The final stage of cognitive development is the formal operational stage where an individual is capable of making logical decisions and solving abstract problems in a more systematic and logical way.
In the preoperational stage, a child lacks to understand relational terms like, lighter, bigger and softer. For instance, there are two lumps of clay, both weighing the same in weight and volume. The first lump of clay is flattened to make it look like a giant cookie while the second lump is made into a small hill. When the child is asked whether do both the lumps of clay measure and weigh the same? The child suggests otherwise and says no. A child at the preoperational stage clearly does not understand relational terms that when the shape changes, the properties do not change. However, this stage shows cognitive growth, as in the sensorimotor stage, a child only learns the concept of object permanance.