According to Piaget, the stages Involve discontinuous (qualitative) change Form an invariant sequence –Stages are never skipped

Sensorimotor Stage (birth-2 years) Newborns have reflexes (motor behavior) and basic perceptual abilities –Refine these innate responses (accommodation) during the first month of life

Gradually become capable of repeating satisfying behaviors that initially occurred by chance

First learn to repeat actions involving their own body –Ex: thumb sucking Then learn to repeat actions involving objects –Ex: shaking rattle

Object Permanence: Understanding that objects continue to exist when they cannot be perceived directly –Infants have some understanding of object permanence at around 8 months

–A-not-B error: Tendency to reach where objects have been found before, rather than where they were last hidden Suggests full understanding of object permanence is not present –Infants make this error until about 12 months of age

From 12 months on, infants increasingly engage in active exploration of objects and their possible functions

At end of sensorimotor stage (18-24 months), mental representations develop –Deferred Imitation: Imitation of a behavior after a period of delay Implies mental representation (memory)

Preoperational Stage (2-7 years) Egocentrism: Tendency to focus on one’s own viewpoint and ignore others’ perspectives –Ex: 3 Mountains Task

Centration: Tendency to focus on one feature of an object or event to the neglect of other important features

Conservation: Understanding that certain physical properties of objects remain the same even when their outward appearance changes

Preoperational children fail conservation tasks because of –Centration –A tendency to focus on static states rather than transformations

Concrete Operations Stage (7-12 years) Understand conservation tasks –Can focus on multiple features of an object or event –Can consider transformations, not just static states

Limitations of Concrete Operations –Children’s logical thinking is limited to concrete information that can be perceived directly Can’t reason about abstract or hypothetical ideas

Formal Operations Stage (12 and older) Ability to think abstractly or hypothetically –“What if... ?”

Can think systematically (scientific reasoning) –Ex: pendulum problem

Criticisms of Piaget’s Theory: Underestimated role of social environment in cognitive development –Ex: Certain experiences (like formal schooling) may promote conservation and other abilities

Does not explain HOW cognitive development occurs –Better description than explanation of children’s cognitive development

The stage model describes children’s thinking as being more consistent than it really is –Ex: Children can solve some conservation problems sooner than others

Infants and young children are more cognitively advanced than Piaget thought –Ex: deferred imitation (and thus mental representation) is present earlier than Piaget thought