Language Development & Cognitive Stages: Child Psychology & Theories

Language development

The process by which humans acquire the ability to perceive, produce, and use words to understand and communicate.

Phonological development

Learning the sounds of a language.

Semantic development

Learning the meanings of words and how to express meaning.

Syntactic development

Learning how to combine words into grammatically correct sentences.

Pragmatic development

Learning how language is used in social contexts.

Language generativity

The ability to use a finite set of words to generate an infinite number of sentences.

Perceptual narrowing

Developmental process in which infants' ability to distinguish phonemes becomes specialized for their native language.

Phoneme

The smallest unit of sound that can change meaning in a language

Infant speech perception

Infants can distinguish all phonemes at birth but lose this ability for non-native contrasts by 10-12 months.

Werker (1989)

Found that 6-8-month-olds detect foreign phoneme differences; 10-12-month-olds do not.

Word learning constraints

Built-in assumptions that help children map words to meanings (e.g., whole object, mutual exclusivity).

Whole object constraint

Children assume a new word refers to a whole object rather than its parts.

Mutual exclusivity constraint

Children assume each object has one label and new words refer to unfamiliar objects.

Overextension

Using a word too broadly (e.g., "dog" for all four-legged animals).

Underextension

Using a word too narrowly (e.g., "bottle" only for baby's bottle).

Joint attention

When a child and caregiver focus on the same object or event; supports language learning.

Pragmatic cues

Social cues such as gaze and tone that help children infer word meanings.

Word gap

The observed difference in language exposure between children from high- and low-income families.

Vocabulary growth

Rapid increase in word learning around 18-24 months ("vocabulary spurt").

Social interactionist perspective

Emphasizes that language learning is supported by social interactions and communication.

Holophrastic period

Stage where a single word expresses a complete thought (e.g., "Mine!").

Telegraphic speech

Two-word utterances that omit small words (e.g., "Mommy go").

Overregularization

Applying grammar rules to exceptions (e.g., "runned," "mouses").

Wug Test (Berko-Gleason, 1958)

Showed that children can apply grammar rules to novel words.

Syntactic bootstrapping

Using sentence structure to infer the meaning of unfamiliar words.

Critical period for language

Time window during which language acquisition occurs most easily (before puberty).

Genie case

Provided evidence for a critical period in first language acquisition.

Newport and Mayberry (ASL studies)

Found that early exposure leads to better grammar proficiency in sign language.

Learning theory (Skinner)

Language learned through reinforcement, imitation, and repetition.

Nativist theory (Chomsky)

Humans are born with innate grammatical knowledge (universal grammar).

Modularity hypothesis

The brain contains a specialized language module separate from general cognition.

Interactionist theory (Bruner, Tomasello)

Language develops through social interaction and communication.

Connectionist theory

Children learn language by detecting statistical patterns in speech input (Saffran, Smith).

Constructivist theory

Children actively construct knowledge through interaction with their environment.

Assimilation

Incorporating new information into existing mental frameworks.

Accommodation

Modifying existing frameworks to fit new information.

Sensorimotor stage (0-2 yrs)

Knowledge through senses and motor actions; object permanence develops.

Preoperational stage (2-7 yrs)

Symbolic thought but egocentric; difficulty taking others' perspectives.

Concrete operational stage (7-12 yrs)

Logical reasoning about concrete events; understands conservation.

Formal operational stage (12+ yrs)

Abstract and hypothetical reasoning.

Egocentrism

Difficulty seeing the world from another's perspective.

Centration

Focusing on one aspect of a situation and ignoring others.

Object permanence

Understanding that objects continue to exist when out of sight.

A-not-B error

Infants look for an object where it was previously found, not where it was hidden.

Deferred imitation

Repeating others' actions after a delay—evidence of mental representation.

Core knowledge theory

Children are born with innate knowledge in key domains (physics, psychology, biology).

Spelke's findings

Infants understand basic object properties and continuity.

Theory of mind

Understanding that others have thoughts, beliefs, and desires different from one's own.

False belief task

Measures understanding that others can hold beliefs that differ from reality.

Vygotsky's sociocultural theory

Cognitive development occurs through interaction with others.

Zone of proximal development (ZPD)

Range between what a child can do alone and what they can do with help.

Social scaffolding

Support from others that helps a child reach higher levels of thinking.

Third-party attention

Observing others' interactions to learn indirectly (Correa-Chávez & Rogoff, 2009).

WEIRD research critique

Western, Educated, Industrialized, Rich, Democratic samples dominate psychology, limiting generalizability.

Bioecological model (Bronfenbrenner)

Development occurs within nested systems—microsystem, mesosystem, exosystem, macrosystem.

Microsystem

Immediate environment (family, school, peers).

Mesosystem

Connections between microsystems (e.g., parent-teacher relationships).

Exosystem

Indirect environments (e.g., parent's workplace).

Macrosystem

Cultural and societal influences.

Evolutionary psychology

Emphasizes adaptive value of slow human development and play for learning.

Information-processing theory

Compares the mind to a computer; focuses on how children process, store, and retrieve information.

Working memory

Actively holds and manipulates information.

Long-term memory

Stores accumulated knowledge.

Executive function

Cognitive control system involving working memory, flexibility, and self-control.

Hostile attribution bias

Assuming others' ambiguous actions are hostile (Dodge & Crick).

General intelligence (g)

A single underlying ability influencing all cognitive performance.

Fluid intelligence

Ability to solve new problems and think flexibly.

Crystallized intelligence

Knowledge from experience and education.

IQ (intelligence quotient)

Standardized score comparing mental age to chronological age.

Three-stratum theory (Carroll)

Hierarchical model with g, broad abilities, and specific skills.

Stability of IQ

IQ scores become relatively stable after age 5.

Word gap and schooling

Environmental input influences IQ and language outcomes.