This study aimed to investigate concerns of validity and reliability in subjective ratings of age-of-acquisition (AoA), through exploring characteristics of the individual rater. An additional aim was to validate the obtained AoA ratings against two corpora – one of child speech and one of adult speech – specifically exploring whether words over-represented in the child-speech corpus are rated with lower AoA than words characteristic of the adult-speech corpus. The results show that less than one-third of participating informants’ ratings are valid and reliable. However, individuals with high familiarity with preschool-aged children provide more valid and reliable ratings, compared to individuals who do not work with or have children of their own. The results further show a significant, age-adjacent difference in rated AoA for words from the two different corpora, thus strengthening their validity. The study provides AoA data, of high specificity, for 100 child-specific and 100 adult-specific Swedish words.

Previous studies suggest that age of acquisition affects the outcomes of learning, especially at the morphosyntactic level. Unknown is how syntactic development is affected by increased cognitive maturity and delayed language onset. The current paper studied the early syntactic development of adolescent first language learners by examining word order patterns in American Sign Language (ASL). ASL uses a basic Subject–Verb–Object order, but also employs multiple word order variations. Child learners produce variable word order at the initial stage of acquisition, but later primarily produce canonical word order. We asked whether adolescent first language learners acquire ASL word order in a fashion parallel to child learners. We analyzed word order preference in spontaneous language samples from four adolescent L1 learners collected longitudinally from 12 months to six years of ASL exposure. Our results suggest that adolescent L1 learners go through stages similar to child native learners, although this process also appears to be prolonged.

This study focuses on adult responses to children's verb uses, the information they provide, and how they change over time. We analyzed longitudinal samples from four children acquiring Hebrew (age-range: 1;4–2;5; child verb-forms = 8,337). All child verbs were coded for inflectional category, and for whether and how adults responded to them. Our findings show that: (a) children's early verbs were opaque with no clear inflectional target (e.g., the child-form tapes corresponds to letapes ‘to-climb’, metapes ‘is-climbing’, yetapes ‘will-climb’), with inflections added gradually; (b) most early verbs were followed by adult responses using the same lexeme; and (c) as opacity in children's verbs decreased, adults made fewer uses of the same lexeme in their responses, and produced a broader array of inflections and inflectional shifts. In short, adults are attuned to what their children know and respond to their early productions accordingly, with extensive ‘tailor-made’ feedback on their verb uses.

We explored the vocabulary and metaphor comprehension of learners of English as an additional language (EAL) in the first two years of UK primary school. EAL vocabulary knowledge is believed to be a crucial predictor of (reading) comprehension and educational attainment (Murphy, 2018). The vocabulary of five- to seven-year-old children with EAL was compared to that of English monolinguals (N = 80). Comprehension was assessed for both verbal (e.g., time flies) and nominal metaphors (be on cloud nine) of varying frequency. Results showed that children in year 2 (age six to seven years) had better comprehension than their younger (age five to six) peers, particularly for low-frequency metaphors. Children with EAL had weaker metaphor comprehension than their monolingual peers, particularly on a reasoning task. The results document how metaphor comprehension develops over the first critical years of schooling and indicates where learners with EAL differ from monolingual peers, thereby supporting targeted vocabulary teaching at primary schools.

This study examines the influence of language-internal (frequency and complexity of linguistic properties), language-external (percent French input, socioeconomic status (SES), and gender), and lexical factors (size of total and French vocabulary) on the phonological production abilities of monolingual and bilingual French-speaking children, aged 2;6. Children participated in an object and picture naming task in which they produced words selected to test different phonological properties. The bilinguals’ first languages were coded in terms of the frequency and complexity of these phonological properties. Results indicated that bilinguals who spoke languages characterized by high frequency/complexity of codas and clusters had superior results in their coda and cluster accuracy in comparison to monolinguals. Bilinguals also had better coda and cluster accuracy scores than monolinguals. These findings provide evidence for cross-linguistic interaction in combination with a ‘general bilingual effect’. In addition, percent French exposure, SES, total vocabulary, and gender influenced phonological production.

Metaphor development in conjunction with verbal intelligence and linguistic competence in middle childhood and at the transition to early adolescence was investigated. 298 individuals between seven and ten years (chronological age) who attended grades two–four (mental age) were tested for metaphor processing by the Metaphoric Triads Task, for linguistic competence (HELD), and verbal intelligence (WISC-III). Chronological age significantly predicted metaphor processing with a breakpoint of 8.2 years regarding identification and comprehension, and 10.2 years regarding preference. Fourth-graders showed highest metaphor processing scores. Verbal intelligence significantly predicted metaphor processing; this effect became stronger with increasing age. Attributional metaphors were best understood and most preferred. Chronological and mental age are associated with metaphor processing in an age span that is seemingly crucial for metaphor development. Verbal analogical reasoning, concept formation, verbal abstraction, and semantic knowledge predicted metaphor comprehension. Understanding facts, principles, and social situations, and resultant inferential verbal reasoning predicted metaphor preference.

Substantial individual differences exist in regard to type and amount of experience with variable speech resulting from foreign or regional accents. Whereas prior experience helps with processing familiar accents, research on how experience with accented speech affects processing of unfamiliar accents is inconclusive, ranging from perceptual benefits to processing disadvantages. We examined how experience with accented speech modulates mono- and bilingual children's (mean age: 9;10) ease of speech comprehension for two unfamiliar accents in German, one foreign and one regional. More experience with regional accents helped children repeat sentences correctly in the regional condition and in the standard condition. More experience with foreign accents did not help in either accent condition. The results suggest that type and amount of accent experience co-determine processing ease of accented speech.

We investigated the association between individual differences in metaphor understanding and Theory of Mind (ToM) in typically developing children. We distinguished between two types of metaphors and created a Physical and Mental Metaphors task, echoing a similar distinction for ToM. Nine-year-olds scored lower than older age-groups in ToM as well as in the interpretation of mental, but not physical, metaphors. Moreover, nine-year-olds (but not older children) who are better in ToM are also better in interpreting mental, but not physical, metaphors. This suggests that the link between metaphor and ToM is stronger when metaphorical interpretation involves mental aspects, and it is more evident in early rather than later childhood.