Human Growth and Development / Unit 3 HGD 0351 worked example, 60 to 90 seconds
The Six Sensorimotor Substages
The idea
Piaget divided the sensorimotor stage into six substages. Simple reflexes, birth to one month. Primary circular reactions, one to four months, repeating actions with the body. Secondary circular reactions, four to eight months, repeating actions on objects. Coordination of secondary circular reactions, eight to twelve months, goal-directed behaviour and object permanence. Tertiary circular reactions, twelve to eighteen months, the child as a little scientist, experimenting. Beginnings of thought, eighteen months to two years, symbolic thought and deferred imitation.
In practice
One child across two years: sucking, thumb-sucking, rattle-shaking, blanket-lifting, dropping food to watch it fall, and imitating a parent's gesture a day later.
Where people slip
The substages describe ways of thinking, not deadlines. Symbolic thought means representing something that is not present; deferred imitation means copying an action after a delay. Both mark the end of the sensorimotor stage. Piaget's ages turned out to underestimate infants, as the next entry shows.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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