Discontinuous (qualitative) change Invariant sequence Stages involve Discontinuous (qualitative) change 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 Infants make this error until about 12 months of age

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

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

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 characteristics of objects remain the same even when their outward appearance changes