Cognitive Development in Infancy
Piaget's Stage-Based Approach to Cognitive Development
Jean Piaget believed that cognitive development occurs in four universal stages:
Sensorimotor
Preoperational
Concrete Operational
Formal Operational
The Sensorimotor Stage (Birth to approx. 2 Years)
This stage is characterized by 6 substages, during which infants construct an understanding of the world by coordinating sensory experiences with physical actions.
Simple Reflexes (first month, e.g., 0-1 month)
Determine early interactions with the world through inborn reflexes.
First Habits and Primary Circular Reactions (approx. 1-4 months)
Actions are coordinated into integrated activities.
Primary Circular Reactions: Repeated motor events that are centered on the infant's own body (e.g., thumb-sucking).
Secondary Circular Reactions (approx. 4-8 months)
Infants act on the outside world to bring about a desired consequence, demonstrating an interest in the environment (e.g., shaking a rattle to hear a sound).
Coordination of Secondary Circular Reactions (approx. 8-12 months)
Infants begin to engage in goal-directed behavior to problem-solve, combining several actions to achieve objectives.
They develop a very basic understanding of object permanence (e.g., searching for a hidden toy).
Tertiary Circular Reactions (approx. 12-18 months)
Infants engage in deliberate experimental variation of actions to bring about desirable consequences, exploring the properties of objects (e.g., dropping a toy from different heights).
Mental Representation (approx. 18-24 months)
Development of symbolic thought, allowing infants to think in symbols and mental images without direct action.
Manifests as the ability of pretend play and deferred imitation (copying actions seen hours or days earlier).
Memory in Infancy
The discrimination of stimuli (the ability to differentiate between two stimuli) demonstrates infant memory.
Memory capabilities significantly increase throughout infancy.
Infantile Amnesia: This refers to the common lack of memory for experiences that occur before the age of 3.
Modern research suggests that while these early memories are encoded, they are not easily retrieved.
Some theories explain infantile amnesia:
Early memories are susceptible to interference from later events.
We can only report memories using the vocabulary available at the time of encoding; as vocabulary changes, retrieval becomes difficult.
Neuroplasticity: The rapid formation of new neural pathways in infancy may interfere with or overwrite old information.
Individual Differences in Infant Intelligence
Defining and measuring intelligence is challenging across all age groups, including infancy.
Developmental Quotient (DQ):
An early measure of infant cognitive development created by Arnold Gesell.
Assessed through observation of hundreds of babies, considering four areas:
Motor skills
Language use
Adaptive behavior
Personal-social behavior
Bayley Scales of Infant Development: A widely used assessment tool.
Mental Scale assesses:
Senses
Perception
Memory
Learning
Problem-solving
Language
Motor Scale assesses:
Gross-motor skills (large muscle movements)
Fine-motor skills (small muscle movements)
Information-Processing Approaches to Infant Intelligence:
These approaches suggest that the speed of infant information processing is correlated with IQ test scores in adulthood.
Visual Recognition Memory: The ability to recognize a stimulus that has been previously seen. This ability relates to later IQ scores.
Cross-modal Transference: The ability to identify with one sense a stimulus that has been initially experienced using another sense (e.g., recognizing an object by sight after only feeling it).
Attention in Infancy
Definition: The cognitive process of selectively concentrating on one aspect of the environment while ignoring others.
Importance: Essential for processing information, learning, and interacting with the world. It lays the foundation for vital cognitive development, including language acquisition, memory, and social skills.
Differences from Older Children and Adults: Infant attention differs in terms of capacity and focus.
Types of Attention:
Focused Attention: The ability to concentrate on a single object or event while ignoring distractions. Crucial for processing information and engaging with specific stimuli. Example: An infant fixating on a colorful toy amidst other items.
Sustained Attention: The ability to maintain focus on a task or stimulus over an extended period. Example: An infant watching a video for several minutes or maintaining focus on a speaker until they finish talking.
Joint Attention: A social-cognitive skill where two individuals share a focus on an object or event. It is important for communication and social interaction and typically develops around 6-12 months of age.
Attention Milestones:
0-3 Months: Focused Attention is observable, with infants briefly fixating on stimuli, especially faces and high-contrast patterns. Example: Infants show a preference for looking at human faces.
3-6 Months: Increased Duration of focus; infants can concentrate for longer periods and are more capable of tracking moving objects. Example: They might follow a toy moving across their field of vision.
6-12 Months: Joint Attention Emerges, as infants begin to follow others' gaze and point, indicating an understanding of shared focus. Example: An infant looks at a toy when a caregiver points to it.
Factors Influencing Attention:
Visual and Auditory Stimuli: Bright colors, movement, and sounds are more likely to capture infants' attention.
Social Interactions: Infants tend to pay more attention to social stimuli, such as faces and voices, particularly those of caregivers, often when using child-directed speech.
Context and Familiarity: Infants show greater attention to both very familiar stimuli and very novel stimuli.
Individual Variation in Attention:
Temperament: Innate behavioral styles influence attention.
Environment: Some environments are more conducive to building attention skills.
Enrichment: The richness of the environment can impact attention.
Amount of social interaction: More interaction can foster attention skills.
Chaos: A chaotic environment can negatively affect attention development.
Parental interaction and sensitivity: Responsive parental interaction enhances attention.
Gestational Age: Full-term infants generally have better attention capabilities.
Healthy Physical Development: Overall physical health contributes to cognitive functions, including attention.
Research Example: Prenatal DHA Supplementation and Infant Attention (Colombo et al.):
Background: Results from randomized trials on the effects of prenatal docosahexaenoic acid (DHA) on infant cognition have been mixed, partly because most trials used global standardized outcomes, which may not be sensitive to DHA's effects on specific cognitive domains.
Methods: Pregnant women were randomized to receive either 600 mg/d of DHA or a placebo during their last two trimesters. Infants of these mothers were then followed with visual habituation tests at 4, 6, and 9 months of age.
Results: DHA supplementation did not affect look duration or basic habituation parameters. However, infants of supplemented mothers maintained high levels of sustained attention (SA) across the first year, whereas sustained attention declined for the placebo group. The supplemented group also showed significantly reduced attrition on habituation tasks, especially at 6 and 9 months.
Conclusion: The findings support the suggestion that prenatal DHA may positively affect infants' attention and regulation of state.
Long Lookers (LL) vs. Short Lookers (SL):
Individual differences in infant attention are theorized to reflect the speed of information processing.
Short Lookers (SL) perform better than Long Lookers (LL) on assessments of memory, language, and intelligence in later development.
At 4 months:
Short Lookers (SL): Exhibit shorter look durations, indicating faster habituation and information processing.
Long Lookers (LL): Exhibit longer look durations, suggesting slower processing or increased attention to detail.
The adult model of feature processing is typically global, inferring that SL's processing bias (focusing on the whole rather than parts) aligns more with mature adult cognition.
Example visual: Given a large 'Z' made of smaller 'N's:
A Short Looker might quickly identify the 'Z' (global feature).
A Long Looker might focus on the individual 'N's (local features).
Heart Rate Defined Phases of Attention (John Richards):
Heart rate (HR) responses to environmental changes can serve as an index for focused attention and inattention in very young infants.
Multisensory Integration
Definition: The integration of audio and visual information into a coherent stream.
Experimental Question: Do participants look at the matching event?
Attention Control: Under the competition of a distractor, do participants still look at the matching event (e.g., will an infant still match a voice to a face if there's a distracting noise or visual)? This tests the robustness of multisensory integration against interference.