Piaget

1. Sensori-motor stage

The first stage of Piaget's cognitive development, occurring from birth to 2 years, characterized by the development of object permanence.

Object permanence

The understanding that objects still exist even when they are not visible.

A not B error

A common mistake of infants aged 8 to 12 months where they search for an object in the location where it was first found rather than where they last saw it placed.

2. Pre-operational stage

The second stage of Piaget's cognitive development from ages 2 to 7, where children start to use language and think symbolically but lack logical reasoning.

Conversation task

A test that evaluates a child's understanding that physical properties remain constant despite changes in shape, length, or position.

Centration

The tendency of pre-operational children to focus on one aspect of a situation while ignoring others.

Irreversibility

The inability of pre-operational children to envision reversing an action.

Egocentrism

The pre-operational child's difficulty in understanding another person's perspective.

3. Concrete operational stage

The third stage of cognitive development (ages 7 to 11) where children can perform operations on concrete objects and understand logical reasoning.

4. Formal operations

The fourth stage of cognitive development starting at age 12, where individuals can think abstractly and hypothetically.

Abstract thinking

The ability to think about concepts and ideas that are not physically present or tangible.

Idealistic thought

Thinking that involves ideals, principles, and values, often developed during the formal operations stage.

Metaphorical thinking

A form of abstract thinking where individuals understand and use metaphors to convey meanings.

If-then thinking

A logical reasoning strategy where one considers the consequences of actions through hypothetical scenarios.

Self-consciousness

An increased awareness of oneself and one's thoughts, usually developing during adolescence.