Jean Piaget - Swiss developmental psychologist; landmark work in cognitive development (some of it came from watching his own kids).

Piaget's Sensorimotor stage (birth to 2):

- before the development of "symbolic thought" (ability to think about things they are not actually sensing)

- no concept of object permanence

- egocentrism

Preoperational (age 2 - approx. 7) - start to use symbolic thought

theory of mind: the development of kids' understanding about the mind; understanding of beliefs, intentions and desires.

second order thought - "meta" thoughts; thoughts about thought

Susie didn't go to the zoo. . . .

Susie INTENDED to go to the zoo, but she missed the school bus

Susie BELIEVED that she WAS she at the zoo, although she was really in a pet store

Susie WANTED (or desired) to go to the zoo, but she didn't get to go because she got sick.

1^st to develop: understanding of desires

later: understanding of beliefs

Along with Theory of Mind comes an understanding of the concept of false belief (appears between ages 3 and 5 usually)

Ability to distinguish between appearance & reality - appears around the same time as understanding of false belief

DeVries (1969) -

inability to distinguish reality/appearance seems to be universal:

1 - occurs in variety of cultures

2 - Simplifying tasks doesn't make it go away

3 - Giving kids "training" on the task doesn't make it go away

gender identification - children's ability to say whether they are a boy or girl.

gender stability - children's knowledge that they will stay the sex they are.

gender constancy - children's knowledge that gender isn't changed by appearance or activities (e.g. wearing barrettes).

Stage at which kids are learning that sex can't (easily) be changed corresponds to Freud's phallic stage

For kids in pre-operational stage, appearance vs. reality problem is particularly hard in visual modality (when things literally LOOK one way but are another)

conservation of:

quantity

number

mass

Piaget's 3^rd stage:

Concrete operational (approx 7 to 11)

transitivity

A > B

B > C

A _ C ?

4^th stage: Formal operational (age 11 on)

abstract thought

analogies

Levinson and Carpenter (1974)

A bird is to air as fish is to:

A bird uses air; a fish uses

5^th stage? Postformal? (develops with age in adulthood)

relativistic thinking

assimilate - fitting an interpretation to a schema

accommodation - changing a schema because of new data

Criticisms of Piaget's model:

1. Observation of limited samples

2. Stages not as rigid, discrete

3. Skills may appear in partial form earlier (methods may have prevented realizing this).

Baillargeon & Graber (1987)

- babies lift wrong cover in object permanence task, but look at correct one.

habituation

Shatz & Gelman (1973) - 4 year-olds adjust instructions to audience

4. Cultural critique

Keysar - adults' inability to ignore own knowledge