Jean Piaget's Stages of Psychosocial Development

Cognitive developmental psychologists like Jean Piaget focus on the development of thought and language. Piaget describes four stages that children pass through on the way to adult thought.

Sensorimotor stage

0 to 2 years - Initially the child relies upon sensory and motor abilities to understand the world. The ability to understand the world by internally representing it in the mind is very limited at first. By the end of this period a gradual transition has been made so that thinking becomes the primary tool for understanding the world. The development of language is a significant result of this new ability. Piaget believed that children are biologically programmed to seek out experiences that will teach them about their world. This view is consistent with the view of others that language learning is also biologically programmed. The development of thinking and language both occur at a very rapid pace.

Preoperational stage

2 to 6 years - Although the child can now use its thinking abilities quite extensively, thought is often illogical and egocentric (limited to personal perspective).

Concrete operational stage

6 to 11 years - Thought now becomes more routinely logical, but is often limited to fairly concrete and previously experienced concepts.

Formal operational stage

11 and above - The child now has the ability to think about abstract concepts on a more regular and logical basis.
the information on this page comes originally from http://www.arc.losrios.cc.ca.us/~stewarm/psy1dev.htm