Special used in the psychological study of infants. One of the many experiments used for features of development of preschool psychology. Developmental psychology is the scientific study of how and why human beings change over the course of their life.
Developmental psychology examines the influences of nature and nurture on the process of human development, and processes of change in context and across time. Watson and Jean-Jacques Rousseau are typically cited as providing the foundations for modern developmental psychology. There are many theorists that have made a profound contribution to this area of psychology. For example, Erik Erikson developed a model of eight stages of psychological development. Sigmund Freud believed that we all had a conscious, preconscious, and unconscious level. In the conscious, we are aware of our mental process.
The preconscious involves information that, though not currently in our thoughts, can be brought into consciousness. Lastly, the unconscious includes mental processes we are unaware of. He believed there is tension between the conscious and unconscious because the conscious tries to hold back what the unconscious tries to express. To explain this he developed three personality structures: the id, ego, and superego.