Cognitive Connie
Understanding cognitive development in infancy
Infants enter the world with powerful capacities for learning, perception, memory, and social interaction. During the first two years, these abilities develop rapidly as infants learn about objects, people, actions, space, and cause and effect.
Key figures
Jean Piaget
1896–1980Detailed the sensorimotor stage through careful naturalistic observation of his own three children. His account of object permanence development and the A-not-B error became foundational challenges for subsequent researchers.
Elizabeth Spelke
1949–Central figure in the core knowledge tradition. Research using VOE and related methods proposed that infants begin life with domain-specific systems for representing objects, agents, number, and space. Her theoretical framework offers an influential alternative to Piaget's constructivist account.
Andrew Meltzoff
1950–Research on neonatal imitation and deferred imitation in infancy. His "like me" framework proposed that imitation provides infants with a mechanism for learning about other people and their actions, connecting early motor behaviour to later social and cognitive development.
Renée Baillargeon
1954–Developed the violation-of-expectation paradigm and used it to provide evidence that young infants may represent the continued existence of hidden objects earlier than Piaget's account predicted. Her work became a central empirical basis for core knowledge theory and has shaped decades of research on infant cognition.
Key concepts
Sensorimotor stage (Piaget)
The first of Piaget's four stages, spanning birth to approximately 2 years. Intelligence is entirely practical — knowing the world through action and perception rather than mental representation. Piaget subdivided it into six substages tracing the development from reflexes through primary, secondary, and tertiary circular reactions to the onset of mental representation (substage 6, ~18–24 months).
Object permanence
The understanding that objects continue to exist when they are no longer perceptible. Piaget held that this is absent in infants under 4–8 months and fully consolidated around 18–24 months, as evidenced by search behaviour. The A-not-B error — searching where an object was previously hidden, not where it was just hidden — marks an intermediate stage around 8–12 months.
A-not-B error
The tendency of 8–12-month-old infants to reach for an object at a previously successful search location (A) even after watching it being hidden at a new location (B). Piaget interpreted this as evidence of incomplete object permanence. Diamond's research suggested it reflects developing executive processes — working memory and inhibitory control — rather than a simple failure to represent the object's location. Other researchers have proposed additional explanations involving attention, motor factors, and task demands, making the A-not-B error a useful case study in how difficult it is to interpret a single infant behaviour.
Violation-of-expectation (VOE) paradigm
A method exploiting the fact that infants tend to look longer at unexpected or unusual events. Infants are shown a possible event and an unexpected or impossible one; if infants look longer at the impossible event, researchers interpret this as evidence that they represented an expectation about what should happen. However, longer looking is an indirect measure — it does not directly reveal the underlying mental representation — and whether such results reflect genuine conceptual knowledge, perceptual preferences, or something else remains an active methodological debate in infant cognition research.
Looking measures vs reaching measures
Infant cognition research uses two broad types of behavioural measure. Reaching tasks (Piaget's method) require infants to act on their understanding — searching, retrieving, or manipulating. Looking-time tasks (Baillargeon's VOE paradigm) infer understanding from how long infants attend to possible versus impossible events. An infant may appear to "know" something in a looking task while still failing an equivalent reaching task. This dissociation matters: it suggests that what a method reveals about cognition depends on which behavioural channel is measured, and that different methods can produce different estimates of when an ability first appears.
Core knowledge theory
Core knowledge theory (Spelke; Baillargeon) proposes that infants begin life with, or rapidly develop, implicit domain-specific systems for representing objects, agents, numbers, and space. These early representations are proposed to provide an initial framework that guides subsequent learning — contrasting with Piaget's constructivist account, in which knowledge is built through infants' interactions with the environment. The theory has been highly influential, but the evidence it rests on — primarily infant looking-time studies — remains debated.
Joint attention
The ability to coordinate visual attention with a social partner toward a shared external object — achieved through gaze following, pointing, and referential looking. Emerges reliably around 9–12 months. A prerequisite for language acquisition and theory of mind, and one of the earliest reliable markers distinguishing typical from atypical social-cognitive development.
Deferred imitation
The reproduction of a modelled action after a delay — interpreted as evidence that the infant encoded and retained a representation of the observed action. Piaget dated deferred imitation to substage 6 (~18 months). Meltzoff showed deferred imitation of novel actions in 9-month-olds after a 24-hour delay, suggesting earlier representational capacity than Piaget's account allows.
Test your knowledge
Sources
Last reviewed September 2026- 1.
Baillargeon, R., Spelke, E. S., & Wasserman, S. (1985). Object permanence in five-month-old infants. Cognition, 20(3), 191–208.
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Landmark VOE study providing evidence that young infants may represent the continued existence of hidden objects before they reliably search for them. Challenged Piaget's sensorimotor timeline; the interpretation of infant looking-time studies remains debated.
- 2.
Piaget, J. (1952). The Origins of Intelligence in Children. International Universities Press.
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Primary source for the sensorimotor stage, based on detailed observations of Piaget's own infants.
- 3.
Meltzoff, A. N., & Moore, M. K. (1977). Imitation of facial and manual gestures by human neonates. Science, 198(4312), 75–78.
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Reported neonatal imitation of facial gestures; the findings became highly influential but have been difficult to replicate consistently and their interpretation remains debated.
- 4.
Diamond, A. (1985). Development of the ability to use recall to guide action, as indicated by infants' performance on AB. Child Development, 56(4), 868–883.
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Proposed that the A-not-B error reflects developing executive control — working memory and inhibitory control — rather than absence of object permanence.
- 5.
Spelke, E. S., & Kinzler, K. D. (2007). Core knowledge. Developmental Science, 10(1), 89–96.
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Influential statement of core knowledge theory, proposing that infants begin life with domain-specific systems for objects, agents, number, and space.