Piaget's theory of cognitive development consists of 4 main stages: 1) Sensory-motor stage (0-2 years): Children understand the world through senses and physical actions. Object permanence emerges around age 2. 2) Pre-operational stage (2-7 years): Symbolic thought and language develop but logical operations have not emerged. Thinking is egocentric and based on perception. 3) Concrete operational stage (7-11 years): Children can think logically and conserve quantities for concrete objects and events. 4) Formal operational stage (11-15+ years): Abstract and hypothetical thinking emerges allowing for planning, propositional thought, and scientific reasoning. Development occurs through processes of assimilation

1. JEAN PIAGET’S
THEORY OF
COGNITIVE
DEVELOPMENT

3. Outline
• (1) General introduction.
• (2) Sensory-Motor period.
• (3) Pre-operational period.
• (4) Concrete operations.
• (5) Formal operations.
• (6) Evaluation.

4. I: TERMS AND CONCEPTS

5. Genetic Epistemology: A
constructivist theory
• No innate ideas...not a nativist theory.
• Nor is the child a “tabula rasa” with the
“real” world out there waiting to be
discovered.
• Instead, mind is constructed through
interaction with the environment; what is
real depends on how developed one’s
knowledge is.

7. How does Piaget describe
developmental change?
• Development occurs in stages, with a
qualitative shift in the organization and
complexity of cognition at each stage.
• Thus, children not simply slower, or less
knowledgeable than adults  instead, they
understand the world in a qualitatively
different way.
• Stages form an invariant sequence.

8. • Cognitive Development-combined result of
maturation of brain & nervous system and
experiences

9. STAGES OF COGNITIVE
DEVELOPMENT
• (1) Sensorimotor (0-2
years)
• (2) Pre-operational (2-7
years)
• (3) Concrete Operational
(7-11 years)
• (4) Formal Operational
(11-16 years)

10. WHAT develops?- Cognitive
structures
• Cognitive structures are the means by
which experience is interpreted and
organized: reality very much in the eye of
the beholder
• Early on, cognitive structures are quite
basic, and consist of reflexes like sucking
and grasping.
• Piaget referred to these structures as
schemes.

11. • Schemes- Strategies used to understand a
particular situation
• Organized ways of making sense of
experience
• Changes with age
• 2 types of schemes: Sensorimotor schemes,
or actions AND Cognitive schemes or
concepts.

12. HOW do cognitive structures
develop?- Cognitive Processes
• Adaptation and Organization
• Through assimilation and accomodation.
• Assimilation: The incorporation of new
experiences into existing structures.
• Accommodation: The changing of an old
structures so that new experiences can be
processed.
• Assimilation is conservative, while
accommodation is progressive.

13. Why accommodate?
• Normally, the mind is in a state of
equilibrium: existing structures are stable,
and assimilation is mostly occurring.
• However, a discrepant experience can lead
to disequilibrium or cognitive “instability”
• Child forced to accommodate existing
structures.

15. Active view of development
• Child as scientist
• Mental structures intrinsically active 
constantly being applied to experience
• Leads to curiosity and the desire to know
• Development proceeds as the child actively
refines his/her knowledge of the world
through many “small experiments”

16. Instructional learning viewed as
relatively unimportant
• Teachers should not try to transmit
knowledge, but should provide
opportunities for discovery
• Child needs to construct or reinvent
knowledge  adult knowledge cannot be
formally communicated to the child
• Limited importance of socio-cultural
context; importance of peer interaction.

19. Piaget
• Sensorimotor Stage
– Newborn uses reflexes to understand world
– Eventually - mental representation
• Object Permanence
• A, not B, error – 8 to 12 month-olds search for an
object in the place where they last found it (A)
rather than in its new hiding place (B).
– Symbolic Capacity

20. II: The Sensorimotor Period
(0-2 years)
• Only some basic motor reflexes grasping,
sucking, eye movements, orientation to
sound, etc
• By exercising and coordinating these basic
reflexes, infant develops intentionality and
an understanding of object permanence.

21. II: The Sensorimotor Period
(0-2 years)
• Intentionality refers to the ability to act in a
goal-directed manner  in other words, to
do one thing in order that something else
occurs.
• Requires an understanding of cause and
effect

22. II: The Sensorimotor Period
(0-2 years)
• Object permanence refers to the
understanding that objects continue to exist
even when no longer in view.
• Need to distinguish between an action and
the thing acted on.

24. Stage 1 (0-1 month)
• Stage of reflex activity.
• Many reflexes like reaching, grasping
sucking all operating independently.
• Objects like "sensory pictures".
• Subjectivity and objectivity fused.
• Schemes activated by chance: No
intentionality.

25. Stage 2 (1-4 months)
• Stage of Primary Circular Reactions.
• Infant’s behaviour, by chance, leads to an
interesting result & is repeated.
• Circular: repetition.
• Primary: centre on infant's own body.
• Example: thumb-sucking.

26. Object concept at stage 2
• Passive expectation: if object disappears,
infant will continue looking to the location
where it disappeared, but will not search.
• In the infant mind, the existence of the
object still very closely tied to schemes
applied to experience

27. Intentions at stage 2
• Intentionality beginning to emerge: infant
can now self-initiate certain schemes (e.g.,
thumb-sucking)

28. Stage 3 (4-8 months)
• Stage of Secondary Circular Reactions
• Repetition of simple actions on external
objects.
• Example: bang a toy to make a noise.

29. Intentionality at stage 3
• Poor understanding of the connection
between causes and effect limits their
ability to act intentionality.
• “Magical causality”  accidentally
banging toy makes many interesting things
happen

30. Object concept at stage 3
• Visual anticipation.
• If infant drops an object, and it disappears,
the infant will visually search for it.
• Will also search for partially hidden objects
• But will not search for completely hidden
objects.

31. Stage 4 (8-12 months)
• Co-ordination of secondary circular
reactions.
• Secondary schemes combined to create new
action sequences.

32. Intentionality at Stage 4
• First appearance of intentional or in
Piaget’s terms, means-end behavior.
• Infant learns to use one secondary scheme
(e.g., pulling a towel) in order that another
secondary scheme can be activated (e.g.,
reaching and grasping a toy)

33. Object concept at stage 4
• Infant will search for hidden objects.
• Does infant understand the object as
something that exists separate from the
scheme applied to find the object?
• No. Evidence?
• A not B error.

34. For Piaget, the error reflected an inability to represent objects
independently of their sensory-motor interactions with those
objects (a lack of the so-called object concept).
POOR MEMORY
Task is easier if locations are very distinct
CAN’T RESIST THE FIRST LOCATION
Reach to A even when object is visible at B
Babies look to B first, but reach to A

35. A trials
The A not B task
1
The A not B task

36. A trials
The A not B task
1
The A not B task

37. A trials
The A not B task
1
The A not B task

38. A trials
The A not B task
2
The A not B task

39. A trials
The A not B task
2
The A not B task

40. A trials
The A not B task
2
The A not B task

41. B trials
The A not B taskThe A not B task

42. B trials
The A not B taskThe A not B task

43. B trials
The A not B task
??

44. A not B error
• Infant continues to search at the first hiding
location after object is hidden in the new
location.
• Object still subjectively understood.
• Object remains associated with a previously
successful scheme.

45. Stage 5 (12-18 months)
• Stage of Tertiary Circular Reactions-
Discovery through Active Experimentation
• Actions varied in an experimental fashion.
• Pursuit of novelty
• New means are discovered.
• Limited to physical actions taken on objects
• Imitation appears

46. Object concept at stage 5.
• Can solve A not B.
• Cannot solve A not B with invisible
displacement (Example from Piaget).

47. Stage 5 and invisible
displacement
• Can only imagine the object as existing
where it was last hidden.
• Invisible displacement requires the infant to
mentally calculate the new location of the
object.

48. Stage 6 (18-24 months)
• Can solve object search with invisible
displacement.
• Infants now mentally represent physically
absent objects.
• Understands object as something that exists
independently of sensory-motor action.

49. Stage 6 (18-24 months)
• Sensori-motor period culminates with the
emergence of the Symbolic function
• An idea or mental image is used to stand-in
for a perceptually absent object
• Deferred imitation

50. Baillargeon’s Test of Object Permanence
3.5-month-olds
Baillargeon, 1987

51. The second study to ask whether infants make inferences about
occluded objects comes from Renee Baillargeon. This is a
habituation/dishabituation study again. In this study, infants were
shown a screen that rotates 180 degrees. They were habituated to
the screens movement. Next, a block was placed placed behind
the screen.
Finally, they were shown one of two test events: one was possible
w/ an object concept the other was impossible.
In this possible event. In this event the screen stopped upon
reaching the block. Which two tenets of the objects concept is this
consistent with? (permanence, independence from other objects)
In the impossible event the screen appeared to rotate through the
object.
Possible event = more novel than impossible event

52. How would you group these?

53. Classification
This grouping is by shape and size and color. It is
multiple classification. The child has to think of three
dimensions at once. In what stage could the child do this?
v

54. Summary
• Sensory-motor period culminates in the
emergence of symbolic representation.
• Object permanence understood.
• Basic means-ends skills have emerged.

55. Piaget – Part 2
Beyond the sensorimotor period

56. III: The pre-operational period
• Symbolic thought without operations.
• Operations: logical principles that are
applied to symbols rather than objects.
• 3 examples: reversibility, compensation,
and identity
• Extraordinary increase in mental
representational activity.
• Language Development- a product of
cognitive development

57. Conservation of Length
The preoperational child would say the one on
the top is longer. Pre-operational children
base their concepts on perception, not logic.

58. Conservation of Length
Are all of these lines the same length? Is one longer?
What would the pre-operational child say?

59. Conservation of Length
Preoperational children are tricked by perception.
The think the one “out front” is longer.

60. Conservation of Area
Which side has more green?

61. Both have the same area of green.
Preoperational children rely on perception and
think the one on the right has more.

62. Conservation of Number
Do these two rows have the same number of balls?
Do these two rows have the same number of balls?
Which has more?

63. Conservation of Number
Pre-operational children think the row on the
bottom has more. Later they develop
one-to-one correspondence.
They understand there is one for this
one, one for that one, and one for that one, etc.

64. • In the absence of operations, thinking is
governed more by appearance than logical
necessity.
• Why Preoperational? – A mental operation
involves logical thought and children at this
stage haven’t acquired the ability to think
logically.
• 2 subperiods-
The Preconceptual Period (2-4 yrs)
The Intuitive Period (4-7 yrs)

65. • Language and Thought- Rapid increase in
language use an outcome of the child’s
developing ability to use symbols
• Make Believe Play- through pretending young
children practice and strengthen newly
acquired representational schemes
• Imaginative, bonding with peer, it is a
representation & so it improves their
representative activity & they can understand
that one thing can be represented in different
ways.

66. - Becomes increasingly detached from real
life conditions
- Less self centered with age
- More complex scheme combinations
• Benefits of Make Believe
• Drawings-
- Scribbles
- Representational shapes and forms
- More realistic

67. A 31/2-year-old’s symbolic
drawing. Halfway into this
drawing, the 31/2-year-old
artist said it was “a pelican
kissing a seal.” A

68. The Preconceptual Period
• Concept- an abstract idea based on grouping objects by
common properties
• Pre concepts: immature concepts held by children
• Egocentrism
• Animistic thinking {child feels inanimate objects have
feelings}
• Syncretic Reasoning {making errors of reasoning by trying
to link ideas that are not always related, eg mother goes to
market and come back with a baby, so next time if the
mother goes to market, she will get another baby}
• Transductive Reasoning

69. THE INTUITIVE PERIOD
• Inability to Conserve
• Understanding is perception bound
• Centration- focus on central aspect, focus only on 1 aspect at a time}
• State vs. Tranformations {Transformations relating different states ignored}
• Irreversibility {the operations are only in 1 direction, eg. You have a sister,
yes; does she has a brother.}
• Lack of Hierarchical Classifications {Eg. 16 flowers shown, out of which 14
yellow, 2 red; so are there more yellow flowers or more flowers?, the child
says yellow flowers
Piaget called it ‘intuitive’ because the child{4-7 yrs) employ certain mental
operations like classification etc, and does not seem to be aware of the principles
used.
Q.Why do clouds move?
A. Because they are pulled when people walk.

70. Pre-operational thinking and
problems of conservation

71. Pre-operational thinking and
problems of conservation
Conservation of liquid

72. Pre-operational thinking and
problems of conservation

73. Pre-operational thinking and
problems of conservation

74. Pre-operational thinking and
problems of conservation

75. Pre-operational thinking and
problems of conservation

76. Pre-operational thinking and
problems of conservation

77. Pre-operational thinking and
problems of conservation

78. • Why do pre-operational children fail
problems of conservation?
• Because their thinking is not governed by
principles of reversibility, compensation
and identity
Pre-operational thinking and
problems of conservation

79. Pre-operational thinking and
problems of conservation
Reversibility: The pouring
of water into the small
container can be reversed.

80. Pre-operational thinking and
problems of conservation
Compensation: A decrease
in the height of the new
container is compensated by
an increase in its width

81. Pre-operational thinking and
problems of conservation
Identity: No amount of
liquid has been added or
taken away.

82. • Why do pre-operational children fail
problems of conservation?
• Because their thinking is not governed by
principles of reversibility, compensation
and identity
• If children applied these principles, they
would conclude liquid is conserved
Pre-operational thinking and
problems of conservation

83. Characteristics of Pre-Operational
Thinking
• Not governed by logical operations
• Consequently, it appears egocentric (e.g., 3
mountains task) and intuitive (e.g.,
conservation tasks)

84. Doll 1 Doll 2
Child
3 Mountains Task

85. Doll 1 Doll 2
Child
3 Mountains Task

86. Conservation of mass

87. Conservation of mass

88. Conservation of mass

89. IV: Concrete operational thinking
(7-12 years)
• Qualitatively different reasoning in
conservation problems.
• Flexible and decentered.
• Co-ordination of multiple dimensions.
• Logical vs. empirical problem solving.
• Reversibility.
• Awareness of transformations.

90. IV: Concrete operational thinking
(7-12 years)
• Physical operations now internalized and
have become cognitive
• Still, logic directed at physical or concrete
problems

91. Operational Thought
• Conservation
• Decentration- {the child can take into account both height
and weight}
• Reversibility ( subtract and add can be done}
• Hierarchical Classification
• Seriation
• Transitive inference
• Spatial reasoning- Distance, Time & Speed and Directions
• Cognitive Maps

92. Limitations of Concrete Operational
Thought
• Abstract Ideas- can do better with abstract
• Horizontal Decalage- child does not neatly move from one
stage to another & might not master some or few
situations.
• Attainment of the earlier concept is essential for
development of the one of greater abstraction.
• Increasing age is essential for progress from one concept to
the next.- as age increases, brain development also
increases.

93. Horizontal decalage
• Different conservation problems solved at
different ages.
• Some claim it is a threat to Piaget’s domain
general view of cognitive development
• Example: volume vs mass
• But, invariant sequence observed.

94. V: Formal operations
• Thought no longer applied strictly to
concrete problems.
• Directed inward: thought becomes the
object of thought.
• Advances in use of deductive and inductive
logic

95. V: Formal operations
• Deductive thought in period of concrete
operations confined to familiar everyday
experience: “If Sam steals Tim’s toy, then
how will Tim feel?”
• Formal operations: “If we could eliminate
injustice, would the world live in peace?”
• Thinking goes beyond experience, more
abstract

97. Inductive reasoning
• Example: Pendulum problem
• Scientific thinking: from specific
observations to general conclusions through
hypothesis-testing

98. Inductive reasoning
• Example: Pendulum problem
How fast?

99. Inductive reasoning
• Formal operational children will
systematically test all possibilities before
arriving at a conclusion

100. • Think Logically
• Abstract Thinking
• Think Realistically
• Form ideals
• Grasp Metaphors
• Introspection
• Think Critically
• Hypothetical reasoning
• Flexible Thinking

101. • ‘What if’ questions
• Hypothetico-Deductive Reasoning
3 basic characteristics-
1)Plan systematically
2)Record the results accurately & objectively
3)Form logical conclusions
• Propositional Thought
- Poker chips experiment

102. • Adolescent Egocentrism
- Self Consciousness: Imaginary Audience
- Self Centeredness: Personal Fable
- Finding faults with Authority Figures
- Argumentativenes
- Apparent Hypocricy

103. VI: Evaluating Piaget
• Difficult.
• An enormous theory.
• Covers many ages and issues in
development.

104. Strengths
• Active rather than passive view of the child.
• Revealed important invariants in cognitive
development.
• Errors informative.
• Perceptual-motor learning rather than
language important for development.
• Tasks.

105. Weaknesses
• The competence-performance distinction

106. Competence
• Knowledge, rules, and concepts that form
the basis of cognition.
• Inferred from behaviour.

107. Performance
• Energy level, interest, attention, language
skills, motivation etc.
• Factors that effect the expression of a
competence.

108. Competence-performance
distinction.
• Piaget attributed infants success (or lack of
success) to competence.
• However, he gave no consideration to
performance factors that may have
constrained the expression of knowledge.
• Example: A not B

109. Performance-competence
distinction and A not B
• A not B errors thought to indicate poor
understanding of objects.
• However, motor components of the task
may constrain the expression of infants
knowledge.
• Example: Baillergeon.
• Object permanence observed in 5 month-
olds using a looking time task.

110. Other examples
• Borke (1975) & the 3 mountains task.
• Bruner (1966) & the liquid conservation
task.
• More detailed task analysis required.

111. Stages?
• Stage like progression only observed if one
assumes a bird-eye view.
• Closer inspection reveals more continuous
changes (Siegler, 1988).

112. Summary
• Piaget’s theory is wide-ranging and
influential.
• Source of continued controversy.
• People continue to address many of the
questions he raised, but using different
methods and concepts.