Cognitive Development With thanks to Jen Brace

Jean Piaget “Father” of cognitive development Studied his children Jacqueline, Lucienne & Laurent Where does knowledge come from?

Piaget’s Theory of Development Stage theory Children think differently in different stages but similarly within a stage Prolonged period of time in a stage, relatively abrupt transition to next stage Four stages Sensorimotor, Preoperational, Concrete Operational and Formal Operational

Piaget’s Theory of Development 3 processes to move between stages Assimilation: Transform incoming information to fit existing way of thinking Accommodation: Adapt thinking to new experiences Equilibration: Integrate pieces of knowledge into unified whole

Sensorimotor Period From birth to ~2 yrs old Actions progress from simple reflexes to deliberate movements Object permanence – realize object still exists even when it can’t be perceived Internal representation – ability to think about objects/events not immediately present

Preoperational Period From ~2 yrs to ~7 yrs Learn to use symbols, signs and language Egocentrism – cannot understand another person’s point of view (but nursery school pics/code switching) Failure of conservation – do not yet understand that quantity remains the same despite appearance

Concrete Operational Period From ~7 yrs to ~11 yrs Thinking becomes systematic, quantitative and logical Success at all conservation tasks – number, solid quantity, liquid quantity Decentration of perception – ability to classify objects in terms of more than one dimension

Formal Operational Period From ~11 yrs to adult Apply logical and systematic thought to abstract problems Deductive reasoning – specific conclusions based on general hypotheses Inductive reasoning – make generalizations based on specific observations Handling multiple variables simultaneously

Strengths of Piaget’s theory Good “feel” for what children’s thinking is like Asks the right questions Covers broad age span Covers broad spectrum of developments in children’s thinking Surprising observations Interplay of content & mechanism

Weaknesses of Piaget’s theory Underestimates competence – children succeed earlier than predicted Can’t explain dissociations – success or failure depends on the way concept is tested No discrete stages - development occurs somewhat gradually or incrementally

Habituation Infants like to look at objects that are new and interesting to them Procedure Familiarization: Object presented repeatedly until infants no longer look at it much New object introduced Method: Infants look longer at new object—allows testing of whether they perceive object as new or old

Occluded rod experiment 4-month-old infants familiarized with A, then presented with either B or C Results – Looked longer at C than B Conclusions Broken rod more novel than unbroken rod Rod in display A was originally perceived as unbroken

Drawbridge experiment 4.5 month old infants Two conditions B is ‘possible’ C is ‘impossible’ Results – Looked longer at C Conclusions Infants know box exists, even when hidden 4.5 month olds understand object permanence

A-not-B experiment Experimenter hides toy under cover A 9-month-old infant successfully retrieves toy After several successful retrievals, experimenter then hides toy under cover B Results - Child still searches under cover A, even though he/she watched the toy being hidden Conclusions – 9 month olds do not understand object permanence

Information-Processing Theories Thinking = information processing Representation of information Processes - applied to representations Constraints - memory limits constrain representation and processing Cognitive development = change in information processing capability Precise analysis of change mechanisms Change produced through continuous self-modification Outcomes of child’s actions change information processing in the future

Memory representations & capacity Working memory span increases with age - Iconic memory capacity also increases with age (1st grade = 2.5 digits, 4th grade = 3 digits, adults = 3.5 digits) Leg-string Infants remembered that kicking made mobile move after 2 months

Rehearsal as information processing Increase in rehearsal speed leads to increase in working memory capacity Older children do better on recall tests because they use rehearsal as a memory strategy

Sociocultural Theories Vygotsky - father of sociocultural theories of development Cognitive development occurs in social interaction Developmental change occurs through internalization of socially shared processes Zone of proximal development Psychological functioning is mediated by cultural tools & language