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 of the drawbridge study• the babies looked longer (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