| For an overview of the stages of sensorimotor thought, it helps to group the six stages into pairs. The first two stages involve the infant’s responses to its own body. | |
| Stage One (birth to 1 month) | Simple reflexes: sucking, grasping, staring, listening |
| Stage Two (1-4 months) | Primary circular reactions (the first acquired adaptations): accommodation and coordination of reflexes Examples: sucking a pacifier differently from a nipple; grabbing a bottle to suck it |
| The next two stages involve the infant’s responses to objects and people. | |
| Stage Three (4-8 months) | Secondary Circular Reactions (making interesting sights last): responding to people and objects Example: clapping hands when mother says “patty-cake” |
| Stage Four (8-12 months) | Coordination of secondary circular reactions (new adaptation and anticipation): becoming more deliberate and purposeful in responding to people and objects Example: putting mother’s hands together in order to make her start playing patty-cake |
| The last two stages are the most creative, first with action and then with ideas. | |
| Stage Five (12-18 months) | Tertiary circular reactions (new means through active experimentation): experimentation and creativity in the actions of the “little scientist” Example: putting a teddy bear in the toilet and flushing it |
| Stage Six (18-24 months) | Mental representations (new means through mental combinations): considering before doing, which provides the child with new ways of achieving a goal without resorting to trial-and-error experiments Example: before flushing, remembering that the toilet overflowed and mother was angry the last time, and hesitating |