Canonical babbling (e.g., "bababa", "mamama") typically emerges at what age, and what is its developmental significance?

A: 2–3 months; it reflects early vocal cord maturation with no linguistic relevance

B: 6–8 months; it marks the onset of syllabic structure and predicts later language development

C: 12–14 months; it coincides with production of first meaningful words

D: 18 months; it indicates the child is falling behind typical phonological development

Correct: 6–8 months; it marks the onset of syllabic structure and predicts later language development

Canonical babbling — reduplicated consonant-vowel sequences — emerges around 6–8 months across all cultures and even in congenitally deaf infants exposed to sign language (who produce manual babbling). It signals that the child has begun to impose syllabic structure on vocalisation. Delayed onset of canonical babbling (past 10 months) is an early clinical marker for risk of language delay.

A toddler calls all four-legged animals "dog". This is an example of:

A: Underextension — using a word too narrowly

B: Overregularisation — applying a grammatical rule too broadly

C: Overextension — using a word too broadly beyond its adult meaning

D: Fast mapping — rapidly forming a preliminary word-to-concept link

Correct: Overextension — using a word too broadly beyond its adult meaning

Overextension occurs when children apply a word to a wider set of referents than adults do — typically based on perceptual similarity (shape, size, movement). It is common in the single-word stage (12–18 months) and reflects the mismatch between the child's concept and the adult lexical boundary, not a failure of understanding. Underextension is the opposite. Overregularisation applies to morphological rules ("goed", "mouses").

Carey & Bartlett (1978) coined "fast mapping" after showing that children could:

A: Learn the sounds of a new language within 24 hours of exposure

B: Map a new colour term ("chromium") to the correct object after a single brief exposure

C: Rapidly recall a list of 20 new words after massed practice

D: Segment words from continuous speech within minutes of hearing a new language

Correct: Map a new colour term ("chromium") to the correct object after a single brief exposure

Carey & Bartlett used the colour term "chromium" — unknown to the children — in a natural request ("hand me the chromium tray, not the red one"). Children as young as 3 correctly selected the unusual-coloured tray and retained a partial mapping days later. Fast mapping describes this ability to form an initial word-to-concept link from minimal exposure, and it underlies the vocabulary spurt seen around 18 months when children acquire 8–10 new words per day.

Berko (1958) showed children a picture of a creature called a "wug" and asked "Now there are two of them. There are two ___." Children who answered "wugs" demonstrated that:

A: They had memorised the plural form of "wug" from previous exposure

B: They could apply grammatical morphology productively to novel items, showing rule knowledge rather than rote learning

C: Children younger than 4 already understand irregular plurals

D: Grammatical competence requires formal instruction

Correct: They could apply grammatical morphology productively to novel items, showing rule knowledge rather than rote learning

The Wug Test demonstrates that children have internalised grammatical rules as productive generative systems, not just memorised individual forms. Since "wug" is a nonsense word they cannot have encountered before, applying "-s" to form "wugs" shows genuine morphological rule knowledge. The same logic applies to overregularisation errors ("goed", "mouses") — they are evidence of rule use, not developmental regression.

Infant-directed speech (IDS), or "motherese", is characterised by higher pitch, exaggerated intonation, and slower tempo. Research by Fernald (1985) suggests its primary function is:

A: Teaching grammar by simplifying sentence structure

B: Attracting and maintaining infant attention, and conveying emotional tone and approval

C: Correcting phonological errors in the infant's babbling

D: Enabling infants to segment the speech stream into individual words

Correct: Attracting and maintaining infant attention, and conveying emotional tone and approval

Fernald (1985) showed that infants prefer IDS to adult-directed speech even in an unfamiliar language, suggesting its prosodic features are intrinsically attention-capturing. Across cultures, IDS uses approval tones (rising contours) and prohibition tones (low, staccato bursts) in ways infants respond to before they understand words. Its role in word segmentation and grammar learning is secondary; its primary function is emotional communication and engagement.

True or False: Deaf children of hearing parents who do not learn sign language fail to develop any structured communicative system.

Answer: False

FALSE. Goldin-Meadow & Feldman (1977) demonstrated that deaf children of hearing parents who were not exposed to sign language spontaneously developed "home sign" — gesture systems with systematic properties including consistent semantic roles, morphology-like modifications, and recursive combination. This is evidence for an innate drive to structure communication even without conventional linguistic input.

Johnson & Newport (1989) studied Chinese and Korean immigrants who arrived in the US at different ages. Their key finding was:

A: Age of arrival had no effect on ultimate grammatical proficiency in English

B: Those who arrived before age 7 performed at native-speaker level; proficiency declined linearly with age of arrival, with a sharp drop after puberty

C: Adults learned grammar faster than children but children learned vocabulary faster

D: Critical period effects were only observed for pronunciation, not grammar

Correct: Those who arrived before age 7 performed at native-speaker level; proficiency declined linearly with age of arrival, with a sharp drop after puberty

Johnson & Newport found that immigrants who arrived before age 7 performed indistinguishably from native speakers on an English grammar test. Those who arrived between 7 and puberty showed gradual decline. Those who arrived after puberty showed poor, highly variable performance with no age-of-arrival effect — they had missed the critical period. This is the most-cited empirical support for Lenneberg's (1967) critical period hypothesis in second-language acquisition.

A 3-year-old who previously said "went" correctly now says "goed". This overregularisation error suggests:

A: Regression — the child is forgetting previously learned forms

B: The child is rule-extracting: applying a regular past-tense rule productively, temporarily overriding a memorised irregular form

C: The child has begun attending to adult speech less carefully

D: Overregularisation is evidence that children learn grammar through imitation

Correct: The child is rule-extracting: applying a regular past-tense rule productively, temporarily overriding a memorised irregular form

Overregularisation is a U-shaped developmental pattern: correct ("went") → incorrect ("goed") → correct again ("went"). The initial correct use is rote-memorised; the error reflects rule extraction (add -ed for past tense). Far from being a mistake, it demonstrates genuine grammatical creativity. Imitation accounts cannot explain it — children never hear "goed" from adults.