Language Development in Infancy and Early Childhood

Emerging Expressive Language

Definition and Early Development

Expressive language refers to the ability to use sounds, signs, or symbols to communicate meaning. This ability typically emerges around 12 or 13 months of age, though the first spoken word can be subtle and easily overlooked. Early attempts at expressive language often occur in specific contexts, and during the first six months of word usage, children may learn as few as 30 words. Each word is learned in connection with particular contexts, highlighting the importance of situational learning in early language acquisition.

• Expressive Language: The use of verbal or nonverbal symbols to convey meaning.

• Contextual Learning: Early words are tied to specific situations or needs.

• Developmental Milestone: First words typically appear around the end of the first year.

• Example: A child may say "milk" only when they see their bottle.

The Vocabulary Spurt

Rapid Vocabulary Growth

Between 16 and 24 months, infants undergo a period of rapid vocabulary expansion known as the vocabulary spurt. The average 16-month-old knows about 50 words, while the average 24-month-old's vocabulary exceeds 300 words. This spurt typically begins once a child has acquired approximately 50 words. Most new words are nouns (names for objects or people), with action words (verbs) appearing later. Infants can distinguish between object names and other word types based on frequency of use.

• Vocabulary Spurt: A rapid increase in word acquisition after the first 50 words.

• Word Types: Nouns are learned before verbs and adjectives.

• Example: Learning "dog," "car," and "mommy" before "run" or "eat."

The First Sentences

Development of Early Sentences

Children begin to combine words into sentences between 18 and 24 months, often after reaching a vocabulary of 100 to 200 words. Prior to this, between 12 and 18 months, infants may combine a single word with a gesture. The earliest sentences are typically two-word utterances, known as telegraphic speech, which include a noun and a verb but lack grammatical inflections. These sentences follow basic syntactic rules, even though they are incomplete.

• Telegraphic Speech: Early two-word sentences that omit less critical words (e.g., "want cookie").

• Inflections: Grammatical markers (e.g., tense, plurality) are usually missing.

• Example: "Mommy go" or "doggy eat."

Individual Differences in Language Development

Variability and Influencing Factors

The rate at which children acquire language varies widely. One significant factor is the number of languages to which a child is exposed daily. Some children begin using individual words as early as 8 months, while others start much later. Most late talkers catch up with their peers by age 6, but those who do not may have poor receptive language skills.

• Influences: Multilingual exposure, individual differences in development.

• Late Talkers: Most catch up by age 6; persistent delays may indicate language disorders.

• Example: A bilingual child may start speaking later but quickly acquires vocabulary in both languages.

Language Development in the First 2 Years

Developmental Milestones (Table 5.3)

The following table summarizes key milestones in language development during the first two years of life:

Age	Milestone
2–3 months	Makes cooing sounds when alone; responds with smiles and cooing when talked to
20 weeks	Makes various vowel and consonant sounds with cooing
6 months	Babbles; utters phonemes of all languages
8–9 months	Focuses on the phonemes, rhythm, and intonation of language spoken in the home; has receptive vocabulary of 20 to 30 words
12 months	Expressive language emerges; says single words
12–18 months	Uses word–gesture combinations combined with variations in intonation
18–20 months	Uses two-word sentences (telegraphic speech); has expressive vocabulary of 100 to 200 words

Language Development Across Cultures

Universal and Cultural Patterns

Language development follows similar patterns across cultures. Babies universally coo before they babble and understand language before they can speak it. The first words typically appear around 12 months, and telegraphic speech emerges around 18 months in all languages. However, the specific word order in early sentences depends on the language being learned. Additionally, the order in which grammatical inflections are acquired varies between languages. For example, Japanese children use pragmatic markers—special words or particles that convey context or emotion—very early in development.

• Universal Milestones: Cooing, babbling, first words, telegraphic speech.

• Cultural Differences: Word order and inflection acquisition depend on language structure.

• Example: Japanese children use markers like "yo" to indicate context or speaker intent.

Chapter Summary

Key Theories and Findings

• Piaget's Theory: Sensorimotor infants progress through six substages, developing symbolic representation, object permanence, and deferred imitation.

• Infant Intelligence: The Bayley Scales of Intellectual Development-III provide a robust measure of infant cognitive abilities.

• Learning Mechanisms: Infants learn through classical and operant conditioning, as well as observation.

• Memory: Infants as young as three months can remember experiences for several days.

• Language Theories: Some theories emphasize parental reinforcement, while others propose innate language processors (e.g., Chomsky's universal grammar).

• Infant-Directed Speech (IDS): High-pitched, repetitive speech helps infants learn language by attracting their attention.

• Environmental Influences: The amount of verbal interaction and socioeconomic status (e.g., poverty) affect language development.

• Developmental Sequence: Cries → coos → babbling → gestures → first words → two-word sentences.

• Late Talkers: Most catch up by age 6; persistent delays may indicate language disorders.

Additional info: Theories such as the nativist perspective (Chomsky) and social interactionist perspective (Vygotsky) provide further context for understanding language acquisition.