CG 63 Children’s Thinking
Lecture 6
Sensorimotor Development
According to Piaget
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, the infant develops intentionality,
object permanence, and mental
representations.
Stage 1 (0-1 month)
The Use of Reflexes
• Many reflexes like reaching, grasping
sucking all operating independently.
• Objects like "sensory pictures".
• Subjectivity and objectivity fused.
• Schemes activated by chance: No
intentionality.
Stage 2 (1-4 months)
First Acquired Adaptations
• Stage of Primary Circular Reactions.
• Infant’s behaviour, by chance, leads to an
interesting result & is repeated.
• Circular: repetition.
• Primary: center on infant's own body.
• Example: thumb-sucking.
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
Imitation & Intentionality at Stage 2
• “Vocal Contagion”
• Mutual imitation of familiar activity if
initiated by infant.
• Intentionality beginning to emerge: infant
can now self-initiate certain schemes (e.g.,
thumb-sucking)
Stage 3 (4-8 months)
Procedures to Make Interesting Sights Last
• Stage of Secondary Circular Reactions
• Repetition of simple actions on external
objects.
• Example: bang a toy to make a noise.
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.
• Visual anticipation of the future positions of objects-- rather than passive viewing of the place where he
saw the object vanish
– “at 0;6(3) Laurent, lying down, holds in his hand a
box five centimeters in diameter. When it escapes
him he looks for it in the right direction (beside
him). I then grasp the box and drop it myself,
vertically, and too fast for him to be able to follow
the trajectory. His eyes search for it at once on the
sofa on which he is lying. I manage to eliminate
any sound or shock and I perform the experiment
at his right and at his left; the result is always
positive. (The Construction of Reality in the Child,
CR)
• deferred circular reactions: an infant can interrupt a
circular reaction involving an object and resume it at
a later time
– “0;8(30) Lucienne is busy scratching a powder box placed
next to her on her left, but abandons that game when she
seems me appear on her right. She drops the box and plays
with me for a moment, babbles, etc. Then she suddenly
stops looking at me and turns at once in the correct position
to grasp the box; obviously she does not doubt that this will
be at her disposal in the very place where she used it
before.” (CR)
• shows that the infant attributes at least some
permanence to the object, but still too closely
associated with a practical situation and previous
activities
Imitation & Intentionality at Stage 3
• Imitation of familiar visible actions
• Poor understanding of the connection
between causes and effect limits their
ability to act intentionality.
Stage 4 (8-12 months)
Coordination of Secondary Schemes
• Co-ordination of secondary circular
reactions.
• Secondary schemes combined to create
new action sequences.
Object concept at stage 4
• Infant will search for hidden object.
• Does infant understand the object as
something that exists separate from the
scheme applied to find the object?
• No. Evidence?
• A not B error.
“at 0;10(18) Jacqueline is seated on a mattress
without anything to disturb or distract her. I
take her parrot from her hands and hide it
twice in succession under the mattress, one
her left, in A. Both time Jacqueline looks for
the object immediately and grabs it. Then I
take it from her hands and move it very slowly
before her eyes to the corresponding place
on her right, under the mattress, in B.
Jacqueline watches this movement but at the
moment when the parrot disappears in B she
turns to her left and looks where it was
before, in A.”
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.
Imitation & Intentionality at Stage 4
• Imitation of novel visible and familiar
invisible events
• 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)
Stage 5 (12-18 months)
Active Experimentation
•
•
•
•
Stage of Tertiary Circular Reactions.
Actions varied in an experimental fashion.
Pursuit of novelty
New means are discovered.
Object concept at stage 5.
• Can solve A not B.
• Cannot solve A not B with invisible
displacement (Example from Piaget).
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.
Imitation at Stage 5
• Imitation of novel invisible events (by trial
and error)
Stage 6 (18-24 months)
Mental Representations
• 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.
Imitation & Intentionality at Stage 6
•
•
•
•
New solutions without overt trial and error
Deferred Imitation
Pretend and symbolic play
Expressive language begins
Summary
• Sensorimotor period culminates in the
emergence of symbolic representation.
• Object permanence understood.
• Basic means-ends skills have emerged.
Baillargeon’s challenge to
Piaget
• 31/2 months were habituated to a screen that
rotated back and forth through a 180° arc
• Later a box was placed behind the screen
– when the screen was in its upright position, it hid the
box behind it from view
• Two kinds of events were set up: a possible and
impossible event
– possible: the screen stopped rotating when it reached
the occluded box
– impossible: screen rotated through a 180° arc, as
though the box was no longer behind it
Results
thelonger
drawbridge
study
• the babiesof
looked
(dishabituated)
•
•
•
•
when the screen moved thru the space where
the box was supposed to be…
represented the existence of the box behind
the screen
understood that the screen could not rotate
through the space provided by the box
expected the screen to stop and were
surprised in the impossible event that it did
not
Baillergeon concluded earlier development of
object permanence than Piaget
– rudimentary knowledge of continued existence of
box (object), but cannot yet organize search
behavior