Cognitive Development

Piaget’s view

• children actively construct knowledge as they grow

• Intelligence evolves through four universal stages driven by basic mental frameworks called schemas, which are updated via assimilation and accommodation

Sensorimotor stage

• the first phase in Jean Piaget's theory of cognitive development, spanning from birth to age 2

• During this period, infants and toddlers build an understanding of the world by combining their basic sensory experiences (seeing, hearing, touching, tasting, and smelling) with physical motor actions

Reflexes

(Birth to 1 month): Infants rely entirely on inborn automatic reflexes, such as sucking and rooting

Primary circular reactions

(1 to 4 months): Babies accidentally discover a pleasurable body action (like sucking their thumb) and intentionally repeat it

Secondary circular reactions

(4 to 8 months): Attention shifts toward the external environment; infants repeat actions to trigger a reaction in their surroundings (e.g., shaking a rattle to hear a sound)

Coordination of reactions

(8 to 12 months): Actions become clearly goal-directed. Infants combine different behaviors to solve simple problems and mimic others

Tertiary circular reactions

(12 to 18 months): Toddlers act like "little scientists," using trial and error to actively experiment with objects and find new ways to interact with them

Mental representations

(18 to 24 months): Children develop the ability to create internal mental symbols. They can solve problems using thought rather than just physical trial and error, and they begin engaging in pretend play

Object permanence

the cognitive understanding that objects, people, and events continue to exist even when they cannot be seen, heard, or touched

A-Not-B error

a common mistake made by infants (typically between 8 and 12 months old) where they search for a hidden object in a familiar hiding place (Location A) even after they watch it get moved to a new hiding place (Location B)

Violation of expectations method

Baillargeon

• a research technique used to study cognitive capacities and core knowledge in preverbal infants

• habituation, test phase, core knowledge

Language development

a natural progression from infant cooing to adult grammar by age five, driven by hearing, brain growth, and daily interaction. The first three years are a critical window for acquiring speech and language

• 0–3 Months: Cooing, smiling, and turning toward sounds.

• 4–6 Months: Babbling with consonant-vowel sounds (like ba-ba or ma-ma).

• 12 Months: Saying first words, pointing, and copying simple sounds.

• 18 Months: Using up to 20–50 words and starting simple two-word phrases.

• 2 Years: Combining words into 3- to 4-word sentences and following basic directions.

• 3–5 Years: Speaking in complex sentences, telling stories, and holding full conversations

Language acquisition device

a hypothetical, innate mental capacity proposed by linguist Noam Chomsky in the 1950s and 1960s to explain how young children rapidly acquire and produce native language

Cooing

refers to the soft, musical, vowel-like sounds (such as "ooh," "aah," and "eee") that infants typically begin making around 6 to 8 weeks of age

Babbling

an early stage of language development where an infant produces meaningless strings of consonant and vowel sounds before speaking recognizable words

First words

infants typically say their first meaningful words between 10 and 14 months of age, marking a major milestone in cognitive and linguistic development

First word combinations

Toddlers typically start combining two words around 18 to 24 months of age

Comprehension vs production

The ability to understand, process, and interpret spoken, written, or signed language (listening and reading) vs. The ability to generate and express language through speech, writing, or sign (speaking and writing)

Vocabulary burst

rapid acceleration in word acquisition that typically happens in toddlers between 18 and 24 months

Underextensions

a common toddler error where a general word is used in an overly restricted way, ex: family pet being called dog without applying same to other dogs

Overextensions

a child uses a single word to refer to a broader group of objects, animals, or ideas than is accurate, ex: calling all 4-legged animals “dog”

Telegraphic speech

a concise communication style where essential content words are used while small grammatical and function words are left out

Specific language impairment

a communication disorder that disrupts the development of spoken or written language in children

Pidgins and creoles

simplified, auxiliary contact language with no native speakers, used for trade or basic communication between groups with different tongues, when a ___ is learned as a first language by the children of a community, it expands into a stable, fully developed ___