Developmental Psychology: The Four Stages Of Human Development

In this chapter, I learned about human development. Types of human development are moral reasoning and cognitive ability. Developmental psychology is the study of how human humans grow, develop, and change throughout life span. In other words, an individual goes the stages of infancy, early middle childhood, adolescence, early and middle adulthood, later adulthood. However, psychologists proposed different theories of development. Some of the psychologists are JeanPiaget and Lawrence Kohlberg.

Piaget proposed that cognitive ability develops in four stages, each involving a qualitatively different way of reasoning and understanding. The four stages are sensori-motor stage, preoperational stage, concrete operational stage, and formal operational stage. The sensori-motor stage occurs during the child's birth until

Infants gain an understanding of the world through their senses and motor activities. After the stage is completed, the child achieves the realization that objects continue to exist when they can be no longer be perceived. During the preoperational stage (ages two through seven years), children acquire symbolic function, which means the understanding that one thing can stand for another. In other words, the child starts to make-believe, such as playing princess or driving a racecar. During the stage, the child exhibits egocentrism, the belief that everyone sees what they see, thinks what they think, etc. For instance, touching someone's bruise, but doesn't feels the pain. The child thinks others can feel her pain. In the concrete-operational stage (seven to eleven to twelve years) , children acquire the concept of conservation. It means the understanding that a given quantity of matter stays the same despite rearrangement or change in its appearance, as long as nothing is added or taken. After the stage, the child will understand reversibility, the the realization that any change in the