Sensorimotor Stage: Piaget's first stage, spanning the first two years of life, during which infants and toddlers "think" with their eyes, ears, hands and other sensorimotor equipment. Through the sensorimotor stage, the child will learn about himself and his surroundings. Thoughts develop from the child's sensation and movement. The child will learn by the end of this stage that certain aspects of his environment exist even when they aren't in sight, which is referred to as object permanence. Sensorimotor ways of interaction aren't only used in this stage but are used throughout life even as adults.
These are the six substages in the Sensorimotor Stage:
  • Reflex activity (0-1 month)-refinement of inborn reflexes such as sucking
  • Primary Circular Reactions (1-4 months)-repetition of interesting acts centered on childs own body (sucking thumb)
  • Secondary Circular Reactions (4-8 months)-repetition fo interesting acts on objects (shaking rattle)
  • Coordination of Secondary Schemas (8-12 months)-combination of actions to solve simple problem
  • Tertiary Circular Reactions (12-18 months)-experimentation to find new ways to solve problems or produce interesting outcomes (splashing water)
  • Beginning of Thought (18-24 months)-first evidence of insight, solve problems mentally, use symbols to stand for objects and actions


    Infants cannot purposely explore the world, they kind of stumbled into it.
    Circular Reaction: provides a special means of adapting their first schemes. The reaction is circular because as the infant tries to repeat the event again and again, a sensorimotor response that originally occurred by chance becomes strengthened into a new scheme.

As children grow, they gain a purpose for performing tasks, because they have a goal and they want to achieve it.



Pre-operational Stage: Piaget's 2nd stage, extending from about 2-7 years in which rapid growth in representation take place but thought is not yet logical. Language is developed. Children are termed to be egocentric during this stage, in which they are not able to understand the point of view of another person. Children more often use objects meant to symbolize something else due to an increase in pretending and playing.

To further prove egocentricism in children during this stage, Piaget constructed an experiement. Children were to view a 3-D display of a mountain scene and were then asked to choose a picture that best represented the scene. Most of the children in this experiment were able to do this. Then they were asked to choose a picture that best represented someone else's point of view from a different viewpoint. Because most children in this stage are unable to understand another person's point of view, most chose a picture representing what they would see instead of what someone else would see.

Concrete Operational Stage beginning around age 7 and ending around age 11, and is when reasoning becomes logical. During this stage, children start to learn to think abstractly. They develop reversibility: children begin to understand that objects can be changed and returned to their original state. This stage also consists of organizing objects into classes and sub-classes, known as classification, where a child is able to identify an object through it's appearance, size, shape, color, etc.

Formal Operational Stage: Begins at about 12 years of age and continues through adulthood (occurs during adolescence). The ability to systematicly think when faced with a problem. These children are also able to evaluate the logic of verbal statements without referring them to real-world circumstances. For example: when asking a child what a sentance means, they are not going to refer to real life instead they are going to tell you exactly what it means. Capacity for abstract, systematic thinking. Enables children to start with a hypothesis, deduce inferences, and isolate and combine variables to see which are confirmed. They evaluate logic without referring to real world circumstances. Mental representations of familiar, large-scale spaces (school, neoghborhood).