1. Cognitive Development
With thanks to Jen Brace

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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

12. 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

13. 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

14. 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

15. 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

16. 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

17. 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

18. 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