Cognitive Development in infancy

Development of the object concept (Piaget)

Jean Piaget proposed that object permanence (the object concept) develops during infancy and reflects a child’s ability to understand that objects continue to exist even when they cannot be seen. According to Piaget, infants learn about the world by acting on their environment and detecting patterns or regularities.

Piaget argued that true object permanence emerges around 8 months of age, and its development corresponds with the six sensorimotor substages of infancy.

Six sensorimotor substages of infancy

1. Reflex Schemas (0–1.5 months)

• Behavior is dominated by reflexes (e.g., sucking, grasping).

• Infants do not search for hidden objects.

2. Primary Circular Reactions (1.5–4 months)

• Infants repeat actions involving their own bodies.

• If an object disappears, they may orient toward where it vanished, but do not actively search.

3. Secondary Circular Reactions (4–8 months)

• Infants repeat actions involving external objects.

• They search for partially hidden objects, but stop searching if the object is completely hidden.

4. Coordination of Secondary Circular Reactions (8–12 months)

• Beginning of object permanence.

• Infants search for completely hidden objects, but only in the original hiding location (this is related to the A-not-B error).

5. Tertiary Circular Reactions (12–18 months)

• Infants experiment with new behaviors.

• They search for an object if they see it moved, but not if it is moved secretly.

6. Beginnings of Symbolic Representation (18–24 months)

• Infants develop mental representations.

• They search for objects in multiple locations, even if the movement occurred out of sight.

Key Idea

Piaget believed that searching for a hidden object requires mental representation—a cognitive ability that allows infants to represent objects in their minds even when those objects are absent.

Development of the Object Concept: Thelen

Esther Thelen proposed an alternative explanation to Jean Piaget for how infants develop the object concept (object permanence).

Instead of believing that object permanence suddenly appears when a specific mental representation “switches on,” Thelen argued that knowledge of hidden objects develops gradually through changes in motor abilities, perception, and experience interacting with objects.

Her dynamic systems theory suggests that cognitive abilities emerge from the interaction of multiple systems, including:

• Motor development (reaching and movement)

• Memory

• Attention

• Experience interacting with objects

• Environmental context

According to Thelen, the ability to search for a hidden object is partly built from movement and motor habits, especially during the first year of life. For example, performance on the A-not-B task is influenced not only by memory but also by the infant’s previous reaching patterns and motor control.

Research supporting Thelen’s theory demonstrated that signs of object knowledge can appear as early as 3 months, much earlier than Piaget’s proposed timeline. These findings challenge Piaget’s claim that object permanence emerges around 8 months and suggest that the development of the object concept is more gradual and distributed across multiple systems rather than appearing suddenly.

Development of Memory:

Memory is a key component of cognitive development and undergoes significant change during infancy.

One important phenomenon is infantile amnesia, which refers to the fact that adults cannot remember experiences from the first few years of life (typically before age 3).

Infantile amnesia occurs because the memory system is still developing during infancy, and early memories are not stored or organized in ways that allow them to be retrieved later in adulthood.

During the first year of life, infants’ memory abilities improve significantly. One important change involves the retention interval, which is the length of time information can be remembered.

• Younger infants have short retention intervals and forget information quickly.

• As infants grow, their retention intervals increase, allowing them to remember experiences for longer periods.

Thus, the development of memory during infancy involves gradual improvements in how information is encoded, stored, and retained, which supports broader cognitive development.

Development of Memory: Mobile Task / Experiment

The mobile task is a classic experiment used to study memory in infants, particularly how long infants can remember an action they previously learned.

The Basic Setup

Researchers place an infant lying on their back in a crib. A ribbon is tied from the infant’s leg to a mobile hanging above them.

• When the infant kicks their leg, the ribbon pulls the mobile and makes it move.

• Infants quickly learn the relationship: kicking → mobile moves

• Because the movement is interesting, infants begin kicking more frequently.

The Testing Phase

In later trials, the ribbon is no longer connected to the mobile. Instead, it is attached to the crib, so kicking does not move the mobile anymore.

The key logic is:

• If the infant remembers the earlier experience, they will kick a lot, expecting the mobile to move.

• If the infant does not remember, their kicking will return to normal levels

Findings About Infant Memory

Researchers found that infants do remember, but their memory is very fragile early in life.

• 2-month-olds:

  • Show memory immediately after learning.

  • However, they forget within minutes or a very short time, showing very short retention intervals.

• 3-month-olds:

  • Can remember the kicking-mobile relationship for up to about a week.

These results show that memory capacity increases rapidly during infancy.

Context-Specific Memory

Another important discovery is that early memories are highly dependent on context.

For example, if an infant learned that kicking moves the mobile when

• The mobile has certain objects, or the mobile is a specific color

  • Then changing those features (new shapes or colors) can cause the infant not to remember to kick.

  • This means early memory is tied to the exact situation in which it was learned.

Developmental Change

As the memory system matures, memories become

• longer lasting (longer retention intervals)

• less context dependent

• more generalized across situations

Development of Memory: Train Task / Experiment

As infants grow older, the mobile task becomes less effective for studying memory. By around 6 months, infants develop greater motor abilities—they can sit up, grab objects, or interact with the mobile in multiple ways. Because they can solve the problem in many ways, the mobile task is no longer a precise measure of memory.

To study memory in older infants (6–18 months), researchers developed the train task.

The Setup

In this experiment, infants sit in front of a toy train setup. In front of them is a large bar they can press or bang. When the infant hits the bar, it activates the train and makes it move along the track.

A plexiglass barrier is placed in front of the train so the infant cannot grab the train directly. This ensures that the only way to make the train move is by banging the bar.

Logic of the Experiment

The procedure works similarly to the mobile task:

1. Infants learn that hitting the bar makes the train move.

2. Later, researchers test whether infants remember this relationship.

3. If infants remember, they will hit the bar more frequently, expecting the train to move.

Findings: Increasing Retention Intervals

The train task revealed that memory duration increases dramatically across infancy.

Approximate retention intervals:

• 6 months: remember for about 2 weeks

• 9 months: remember for about 5.5 weeks

• 10 months: remember for about 7 weeks

• 15 months: remember for about 10 weeks

• 18 months: remember for about 13 weeks

What This Shows

These findings demonstrate that:

• Infant memory improves steadily with age

• Retention intervals grow longer over time

• Cognitive development involves gradual strengthening of memory systems

Challenges to Jean Piaget (competence vs. performance distinctiondistinction)

• Piaget argued that infants’ abilities reflect their true competence, and errors show a lack of knowledge

He distinguished:

• Competence = what a child knows

• Performance = how a child demonstrates that knowledge

Challenge: Research shows infants’ memory is rapidly developing and not fixed in the first year

• Memory is supported by lower-level systems:

  • perception

  • attention

  • motor abilities

  • encoding & retrieval processes

Bottom-up view: Higher-level cognition (e.g., memory, object permanence) emerges from these basic systems

• Therefore:

  • Infants may fail tasks not because they lack knowledge, but because:

    • Memory demands are too high

    • Motor responses are difficult

    • attention is limited

• Key implication:
  → Violates Piaget’s assumption that performance = competence
  → Infants may have greater underlying knowledge than Piaget claimed

Origins of Knowledge: Nativist

New cards

Origins of Knowledge: Nativist

🧠 Core Idea

Nativists believe babies are born with built-in (innate) knowledge

👉 This is called “core knowledge”

---

👶 What Babies Know (According to Nativists)

Babies already understand basic ideas like:

• Number

• Objects

• Physics

👉 They don’t need to learn these from scratch

---

🔍 Role of Experience

Experience is:

• ❗ Less important

👉 Babies don’t need much learning — they already “know” a lot

---

⚖ Competence vs Performance

• Competence = what babies actually know

• Performance = what they can show/do

👉 Babies may know more than they can show (because of limits like memory, motor skills, attention)

---

🧪 How They Study Babies

Use “impossible event” experiments

---

😲 Impossible Event Paradigm

Babies see:

• Something normal (possible)

• Something weird/impossible

👉 If babies look longer at the impossible event, it means:

• They are surprised

• So they must have expected something else

---

🎯 Key Idea

Looking longer =
➡ “This violates what I expected”

👉 Shows babies had knowledge already

Origins of Knowledge: Constructivists

Origins of Knowledge: Constructivists

🧠 Core Idea

Constructivists believe:
👉 Babies build knowledge over time through experience

---

🌍 How Learning Happens

Babies learn by:

• Seeing (perceiving)

• Doing (acting on the world)

👉 Learning = interaction with the environment

---

👶 Role of “Immature” Behavior

Babies aren’t bad at things for no reason

👉 Their mistakes actually:

• Help them learn

• Create opportunities to improve

---

👀 Importance of Perception

Perception is:

• ⭐ VERY important

👉 Babies learn from:

• What things look like

• What they hear, touch, see

---

🧬 Biology + Experience

Babies are not blank slates, BUT:

• Their biology is designed to learn from experience

👉 Development =

• Brain + Experience working together

---

🎯 Key Idea

Knowledge is:

• ❌ NOT fully inborn

• ✅ Built step-by-step through experience

---

🔥 Simple Example

A baby doesn’t understand number at first

👉 They first learn:

• “how much stuff” (perception)

👉 Then later:

• actual numbers

Baillargeon 2004

NATIVIST IDEA

Violation of Expectancy (VOE) Paradigm

Since infants can’t talk, researchers measure looking time:

• Habituation → decreased looking (learning occurred)

• Dishabituation → increased looking (something unexpected)

👉 Infants look longer at events that violate their expectations

---

Renée Baillargeon and “Impossible Events”Method

1. Infants are habituated to a possible event

2. Then shown:

   • A possible event OR

   • An impossible event (e.g., object passing through a solid barrier)

Habituation test: object placed behind screen, then screen rotates up and into the objec

Finding

• Infants look longer at impossible events (object passing through a solid barrier)

Conclusion

• Infants have early (possibly innate) knowledge of:

  • Object permanence

  • Physical properties (e.g., solidity)

👉 Supports:

• Competence ≠ performance

• Infants may know more than they can act on

Problems with Baillargeon: Cashon and Cohen Study

CONSTRUCTIVIST IDEAS

Cashon and Cohen are basically testing this idea:

👉 Do babies react because they already know what’s possible/impossible,
OR because they just learned something during the experiment?

---

They say:

If babies truly have innate knowledge, then what they saw during habituation shouldn’t matter.

👉 Meaning:
Even if you show them impossible events over and over, they should STILL recognize:

“That’s impossible”

---

So here’s the key test:

• First, babies are habituated to impossible events (they get used to them)

• Then, they are shown a possible event

---

If babies have innate knowledge, they should think:

“This possible event is normal”

👉 So they should NOT react

---

BUT instead:

👉 Babies DO react (look longer) at the possible event

---

💡 What that means (this is the important part)

Babies are NOT thinking:

“This is possible vs. impossible”

They are thinking:

“This is DIFFERENT from what I just saw”

---

So the “violation” is NOT:

• ❌ breaking an inborn rule about physics

It IS:

• ✅ breaking the pattern they just learned during habituation

---

🎯 What Cashon & Cohen conclude

Baillargeon thought:
👉 Babies have inborn knowledge of physics

But actually:
👉 Babies are just responding to:

• what they learned during the experiment

• what is familiar vs. new

Power and pitfalls of the violation of expectations method

Wynn Development of numerosity

Core Claim (Nativist View)

Wynn argued that infants are born with innate numerical knowledge, sometimes called a “core number system.”

• Infants can represent small quantities (e.g., 1, 2, 3)

• They can perform simple arithmetic expectations (like 1 + 1 = 2)

👉 This knowledge is present very early, not learned from scratch

Key Evidence: Violation of Expectancy

• Infant sees 1 object placed behind a screen

• Then another object is added (1 + 1)

• Screen is lifted to reveal:

  • Possible outcome: 2 objects

  • Impossible outcome: 1 object

Result

• Infants look longer at the impossible outcome

👉 Interpretation:

• Infants expected 2 objects

Suggests basic arithmetic understanding

Wynn U-shaped developmental pattern:

Wynn proposed a U-shaped developmental pattern:

1. Early infancy

   • Strong nonverbal numerical competence

   • Infants succeed in tasks

1. Toddler period (learning language)

   • Performance may decline

   • Number words and language interfere

1. Later development

   • Performance improves again

   • Children integrate language + numerical concepts

Competence vs. Performance

Wynn’s findings support the idea that:

• Infants may have competence (knowledge)

• But their performance fluctuates depending on:

  • Language development

  • Task demands

👉 So:

• Knowledge is not lost, just harder to express at times

Clearfield & Mix

Constructivist VIEW

🧠 Core Idea

Babies do NOT count.

They understand:

• How much stuff there is (amount/size)

They do NOT understand:

• How many things there are (number)

---

🧪 Study Setup

Babies see:

• 2 small squares

• then 1 big square

👉 Both have the same total size (same amount of stuff)

---

👶 What Babies Expect

If babies understood numbers, they would think:

• “2 is different from 1”

👉 They should be surprised

---

👀 What Actually Happens

Babies are NOT surprised
(they don’t look longer)

---

💡 Why?

Because babies think:

• “This is the same amount”

👉 They ignore number and focus on size/amount

---

🎯 Key Finding

Babies track:

• ✅ Amount (how big / how much)

NOT:

• ❌ Number (1 vs 2)

---

🔥 Big Idea

Early thinking =
➡ “Does this look like the same amount?”

NOT
➡ “Is this the same number?”

---

🧩 What develops later

Over time, babies learn:
➡ how to actually count and understand numbers

Integrative approaches: Gottlieb

Gottlieb is basically saying:

👉 Development doesn’t come from just one thing

Instead, it comes from many sources working together

---

These sources include:

• Biology (genes, brain)

• The environment (what the baby experiences)

• The baby’s own behavior

---

He focuses on what’s happening inside the child, but also how that connects to the outside world.

---

🎯 What this means

A baby’s development is shaped by:

• Their body and brain

• Their experiences

• Their actions

👉 All interacting at the same time

Integrative approaches: Bronfenbrenner

👉 A child’s development is affected by different layers of their environment

---

🧠 Core Idea

Development is shaped by everything around the child, from close relationships to big cultural beliefs

---

🏠 Microsystem (closest level)

This is what the child interacts with directly

Examples:

• Parents

• Siblings

• Home life

• School

• Friends

• Neighborhood

👉 These are daily, face-to-face interactions

---

🔗 Mesosystem (connections between things)

This is how parts of the microsystem connect with each other

Examples:

• Parent–teacher relationships

• Home affecting school life

• Religion influencing family life

👉 It organizes the child’s everyday experiences

---

🏢 Exosystem (indirect influences)

These don’t involve the child directly, but still affect them

Examples:

• Parents’ jobs

• School boards

• Government

• Media

👉 These shape the child’s life indirectly

---

🌍 Macrosystem (big picture)

This is the largest level

Includes:

• Culture

• Beliefs

• Values

• Ideologies

👉 These influence all the other systems

---

🔁 Key Idea

All these systems are connected

👉 Big cultural beliefs → affect institutions → affect daily life → affect the child

---

👶 Important Point

The child is NOT passive

👉 They don’t just receive influence

They also:

• Bring their own behavior

• Shape their interactions

Integrative approaches: Faust et al.

👉 Development is NOT just genes or just environment

Instead, it exists on a spectrum (a range)

---

🧠 Core Idea

Different behaviors come from different mixes of influences

👉 Some are more genetic
👉 Some are more learned

---

📊 The Spectrum

On one side (LEFT):

• More innate (inborn) behaviors

• Example: reflexes
  👉 These happen automatically and don’t need learning

---

On the other side (RIGHT):

• More learned/social behaviors

• Example: communication, social skills
  👉 These cannot develop without other people/environment

---

🎨 What the Colors Mean

• Origin (reflexes) → basic, inborn actions

• Green (perception) → what babies can see/hear

• Blue (social/communication) → interaction with others

👉 These show different types of abilities developing

---

🔁 Key Idea

No behavior is 100% genes or 100% environment

👉 Everything is a mix, just in different amounts

---

🎯 What This Means

• Reflexes → mostly biological

• Perception → mix

• Social skills → mostly learned

👉 But ALL involve both genes + experience