Cognitive Development in Infancy: Piaget’s Sensorimotor Stage and Beyond

Cognitive Development in Infancy

Introduction

This section explores the remarkable cognitive changes that occur during infancy, focusing on the first two years of life. It covers foundational theories, key milestones, and recent research findings in the field of developmental psychology.

5.1 Cognitive Changes and Intelligence in Infancy

Overview

• Infancy is marked by rapid and consistent cognitive advances across different environments.

• Significant steps toward cognitive maturity are taken in the first two years of life.

5.1.1 Piaget’s Sensorimotor Stage

Milestones of Piaget’s Sensorimotor Stage

• Infants assimilate new information into existing sensory and motor schemes.

• They accommodate these schemes based on new experiences.

• This period is known as the sensorimotor stage, where infants develop and refine sensorimotor intelligence.

Substages of the Sensorimotor Stage

• Substage 1 (0–1 month): Infant is tied to the immediate present and does not plan actions.

• Substage 2 (1–4 months): Primary circular reactions – Simple repetitive actions centered on the infant’s own body.

• Substage 3 (4–8 months): Secondary circular reactions – Repetitive actions involving external objects.

• Substage 4 (8–12 months): Means-end behavior – Purposeful actions to achieve specific goals.

• Substage 5 (12–18 months): Tertiary circular reactions – Deliberate experimentation with variations of previous actions.

• Substage 6 (18–24 months): Ability to manipulate mental symbols, solve problems by thinking, and learn to use tools.

Table: Milestones in the Development of Sensorimotor Intelligence

Milestone	Description
Primary circular reactions	Simple repetitive actions organized around a baby’s own body
Secondary circular reactions	Repetitive actions oriented around external objects in a baby’s environment
Means-end behavior	Purposeful behavior carried out in pursuit of a specific goal a baby is pursuing
Tertiary circular reactions	A baby’s deliberate experimentation with variations of previous actions

Table: Review of Sensorimotor Substages

Substage	Average Age	Primary Technique	Characteristics
1	0–1 month	Reflexes	Use of built-in schemes or reflexes; limited imitation; no ability to integrate information from several senses.
2	1–4 months	Primary circular reactions	Accommodation of basic schemes; actions repeated for their own sake; limited to own body.
3	4–8 months	Secondary circular reactions	Awareness of events outside own body; beginning understanding of object concept.
4	8–12 months	Coordination of secondary schemes	Intentional, goal-directed behavior; transfer of information between senses.
5	12–18 months	Tertiary circular reactions	Experimentation with new ways of playing; trial-and-error exploration.
6	18–24 months	Beginning of mental representation	Use of symbols to represent objects/events; able to solve problems by thinking about them.

Changes in Means-End Behavior

• Means–end behavior becomes more sophisticated in later substages.

• By 24 months, infants can store observations in memory and act more directly on the world.

• Early stages show little independent action; by 18–24 months, infants are more proactive.

Object Permanence

Development of Object Permanence

• Object permanence is the understanding that objects continue to exist even when they cannot be seen.

• Develops gradually across substages 2–6.

• Early signs appear around 2 months; by substage 3, infants search for dropped toys.

• Substage 4 is marked by the A-not-B error (searching for an object where it was last found, not where it was hidden).

• By substage 6, infants resolve the A-not-B error and use more logical search strategies.

Imitation

Development of Imitation in Infancy

• Infants imitate actions of others from the first few months of life.

• Facial gesture imitation emerges by substage 4, requiring intermodal perception.

• Deferred imitation is the ability to imitate an action after a delay, requiring internal representation.

5.1.2 Challenges to Piaget’s Explanation of Infant Cognitive Development

Modern Research Findings

• Recent studies suggest Piaget underestimated infants’ cognitive abilities.

• Infants show understanding of object movements and can imitate at younger ages than Piaget proposed.

Other Research on Object Permanence

• Piaget’s original studies required motor skills (e.g., moving a blanket), but newer methods (e.g., "looking" studies) show object permanence as early as 4 months.

• Infants can mentally represent objects hidden from view, but understanding may depend on the experimental context.

• Object permanence is now seen as a process of elaboration, not just discovery.

Other Research on Imitation

• Imitation of hand movements and object actions improves from 1–2 months onward.

• Imitation of complex actions develops around 15–18 months.

• Newborns can imitate certain facial gestures; deferred imitation is observed as early as 6 weeks.

• Infants learn through modeling, supporting Piaget’s sequence but at earlier ages.

5.1.3 Alternative Approaches

Object Concept and New Theories

• Elizabeth Spelke and colleagues propose infants are born with built-in assumptions guiding their interactions with objects.

• Connected-surface principle: When two objects are connected, infants assume they belong to the same object.

• Violation-of-expectations method: Infants show surprise at impossible outcomes, indicating awareness of object properties as early as 2–3 months.

Other Studies of Infants’ Understanding of Objects

• Renée Baillargeon: Infants develop and modify hypotheses about how objects move and connect.

• Leslie Cohen: Infants respond to novelty, indicating cognitive processing of new information.

• Understanding of objects forms the foundation for applying object concepts in the real world.

Figures and Applications

• Baillargeon’s Cube Arrays: Used to test infants’ understanding of object solidity and continuity.

• Apparatus for Predicting Object Location: Demonstrates infants’ ability to anticipate where an object will appear, reflecting cognitive development in object tracking.

Example: The game of peek-a-boo illustrates the development of object permanence, as infants gradually learn that people and objects continue to exist even when out of sight.

Additional info: These findings have important implications for understanding early learning, memory, and the nature of intelligence in infancy, and they inform both developmental theory and practical approaches to early childhood education.