PY2DAL 2) Language Development

A set of 30 vocabulary flashcards covering the biological, cognitive, morphological, and social stages of child language development.

Voice Onset Time (VOT)

The length of time between when a consonant is released and when the vocal cords start vibrating.

Categorical perception

The perceptual phenomenon where continuous acoustic changes in a stimulus are perceived not as gradual variations, but as belonging to discrete perceptual categories.

High Amplitude Sucking (HAS) paradigm

An experimental dishabituation method used to measure speech discrimination in $1$- to $4$-month-old infants based on sucking rate changes in response to novel phonetic stimuli.

Universal learners

The characterization of young infants who possess the innate capacity to discriminate phonetic contrasts across all world languages, before tuning exclusively to native contrasts.

Speech segmentation

The developmental ability of infants to isolate individual word boundaries from within a continuous, unbroken auditory stream of spoken language.

Transitional probability (TP)

A statistical cue between syllables that infants compute to detect word boundaries, exhibiting higher probability within words ($\text{TP} = 1.0$) and lower probability across word boundaries ($\text{TP} = 0.33$).

Vocabulary spurt

A rapid and sudden surge in the number of words an infant understands and produces, commonly emerging around $16\text{--}24\text{ months}$ of age.

Word

An arbitrary symbolic mapping between a specific speech sound and its meaning.

Fast mapping

The cognitive ability of children around $2\text{ years}$ of age to learn new words and their underlying meanings rapidly after only a single, brief exposure (Carey, 1978).

Naming insight

The cognitive realization discovered by young children that all objects and entities have names, proposed by Kamhi (1986) as a cause for the vocabulary spurt.

Overregularisation

A morphological error where a child overapplies a regular inflectional rule to an irregular word, generating forms like 'goed' instead of 'went' or 'mouses' instead of 'mice'.

U-shaped learning curve

A morphological developmental trajectory where performance begins high via rote imitation ('went'), temporarily declines due to overregularisation of rules ('goed'), and recovers as irregular exceptions are learned.

The Wug Test

An experimental morphological task designed by Jean Berko (1958) that uses pseudo-words (e.g., 'wug') to demonstrate that children deduce and apply productive grammatical rules rather than merely repeating heard forms.

Holophrases

Single words paired with physical gestures emerging around $13\text{ months}$ of age that function communicatively as complete 'two-word sentences' (Bates et al., 1987).

Telegraphic speech

Two-word utterances appearing around $18\text{--}24\text{ months}$ that convey meaning while omitting grammatical function elements such as tense inflections or articles (e.g., 'Give juice').

Grammar explosion

A language development milestone occurring between $27\text{--}36\text{ months}$ characterized by the emergence of $3\text{- or }4\text{-word}$ sentences containing verbs, negations, and morphemes.

Pragmatics

The component of language dealing with communication, discourse rules, conversational turn-taking, and how linguistic utterances are modified to fit social contexts.

Speech registers

The stylistic adaptations a speaker makes to their speech based on the listener's identity and the formality of the social situation (Sonnenschein, 1988).

Phonology

The branch of linguistics and language development concerned with the speech sounds, suprasegmentals, and systematic sound rules of a specific language.

Semantics

The domain of language concerned with vocabulary and the linguistic meanings of words and components of words.

Syntax

The grammatical subsystem of language governing word order, sentence structure, and morphology.

Language Acquisition Device (LAD)

An innate, biological cognitive system proposed by Noam Chomsky that provides infants with universal structural principles to facilitate language acquisition.

Universal Grammar

Chomsky's theoretical framework of innate, invariant principles and parameters that guide and constrain grammatical development across all human languages.

Interactionist theories

Frameworks asserting that language emerges through dynamic interactions between biological predispositions, cognitive growth, domain-general mechanisms, and rich social scaffolding.

Thalamocingulate division

A brain area identified in Paul MacLean's Triune Brain model that activates during maternal perception of infant crying, mediating mother-infant attachment behaviors (Lorberbaum et al., 2002).

Broca's area

A cortical region located in the frontal lobe dedicated to speech production; lesioning causes Broca's aphasia, characterized by short, telegraphic, and halting expressive language.

Wernicke's area

A cortical region situated in the temporal lobe essential for language comprehension; damage results in Wernicke's aphasia, marked by fluent-sounding speech devoid of meaning.

Lateralization

The neurological principle whereby specific cognitive and psychological functions are localized primarily within one of the cerebral hemispheres.

Canonical babbling

A prelinguistic developmental stage occurring between $35\text{ weeks}$ and $1\text{ year}$ characterized by repetitive syllable vocalizations that begin to sound like actual words.

Complex/modulated babbling

A prelinguistic vocal stage between $10\text{--}15\text{ months}$ characterized by the communicative use of babbling and deliberate variation of intonation and stress patterns.