The Cross-linguistic Lexical Task (CLT; Haman, Łuniewska & Pomiechowska, 2015) is a vocabulary task designed to enable cross-linguistic comparisons both across and within (bilingual) children. In this paper we assessed the validity of the CLT as a measure of language proficiency in bilingual children, by determining the extent to which (i) age-matched, monolingual Spanish-speaking and Dutch-speaking children obtained similar scores, (ii) the CLT correlated with other measures of language proficiency in monolingual and bilingual children, and (iii) whether the factors underlying the CLT's construction, i.e., target words’ estimated Age of Acquisition and Complexity Index, were predictive of children's scores. Our results showed that, while the CLT correlated with other measures and is therefore a valid means of tapping into language proficiency, caution is required when using it to compare children's language proficiency cross-linguistically, as scores for Dutch-speaking and Spanish-speaking monolinguals sometimes differed.

Previous studies across languages (English, Spanish, French) have argued that perceptual salience and cue reliability can explain cross-linguistic differences in early comprehension of verbal agreement. Here we tested this hypothesis further by investigating early comprehension in Greek, where markers have high salience and reliability (compared to Spanish and English) predicting early comprehension, as in French. We investigated two and three-year-old Greek-speaking children's ability to distinguish third person singular and plural agreement in a picture-selection task. We also examined the frequency of these morphemes in child-directed speech to address input effects. Results showed that three-year-olds are sensitive to both singular and plural agreement, earlier than children acquiring English and Spanish, but later than French, and despite singular agreement being more frequent than plural agreement in the child corpus. These findings provide further support for the role of salience and reliability during early acquisition, while highlighting a potential effect of morpheme position.

From a socio-cultural perspective, language offers a means for children to communicate with and learn from others through interaction: language is the medium through which young children are provided cognitive, social, and emotional support in interactions with caregivers, siblings, and peers; and children characterized as dual language learners (DLLs) have in common that they receive this developmental support in two different languages. However, due to variations in socioeconomic factors, ethnic/immigration background, and language socialization practices, DLLs display considerable variability in their first- and second-language proficiency (McCabe, Tamis-LeMonda, Bornstein, Cates, Golinkoff, Guerra, Hirsh-Pasek, Hoff, Kuchirko, Melzi, Mendelsohn, Páez & Song, 2013).

This paper investigates whether typical stress patterns in English nouns and verbs are available as a prosodic cue for categorisation and accelerated word learning during first language acquisition. The stress typicality hypothesis states that left-stressed nouns and right-stressed verbs should be acquired earlier than the reverse configurations if stress effectively signals lexical class membership. In this view, class-typical stress patterns are expected to facilitate learning of novel items. A series of generalized additive models (GAMs) based on a comprehensive set of lexical data (CELEX) as well as a large set of age-of-acquisition (AoA) and concreteness ratings reveals that stress typicality plays a minor role in early acquisition, as it is generally superseded by a preference for left-hand (or ‘trochaic’) patterns in both nouns and verbs. This may be explained by general cognitive constraints (perceptual salience and recency) or exposure to the dominant pattern in the ambient language.

This study investigated the acquisition of word-patterns and roots in the nominal system of the spoken language of Palestinian Arabic (PA) and its distance from Standard Arabic (StA). It described, analyzed, and quantified the nominal system (roots and word-patterns) as reflected in the language corpus of Palestinian-Arab kindergarteners 3 to 6 years old. The results showed that non-linear derived nouns (deverbal nouns) are the most frequently used category (49.5%). Primitive nouns comprise 43.1% of the nouns, whereas linear derived nouns barely exist before children start school (0.3%). Additionally, the results showed that half of the nouns were built from common word-patterns and roots between PA and StA, whereas 30% of the nouns were constructed from different word-patterns with common roots. Although PA and StA have much in common morphologically, there exists a significant degree of divergence.

The rate at which young children are directly spoken to varies due to many factors, including (a) caregiver ideas about children as conversational partners and (b) the organization of everyday life. Prior work suggests cross-cultural variation in rates of child-directed speech is due to the former factor, but has been fraught with confounds in comparing postindustrial and subsistence farming communities. We investigate the daylong language environments of children (0;0–3;0) on Rossel Island, Papua New Guinea, a small-scale traditional community where prior ethnographic study demonstrated contingency-seeking child interaction styles. In fact, children were infrequently directly addressed and linguistic input rate was primarily affected by situational factors, though children's vocalization maturity showed no developmental delay. We compare the input characteristics between this community and a Tseltal Mayan one in which near-parallel methods produced comparable results, then briefly discuss the models and mechanisms for learning best supported by our findings.

Infants struggle to understand familiar words spoken in unfamiliar accents. Here, we examine whether accent exposure facilitates accent-specific adaptation. Two types of pre-exposure were examined: video-based (i.e., listening to pre-recorded stories; Experiment 1) and live interaction (reading books with an experimenter; Experiments 2 and 3). After video-based exposure, Canadian English-learning 15- to 18-month-olds failed to recognize familiar words spoken in an unfamiliar accent. However, after face-to-face interaction with a Mandarin-accented talker, infants showed enhanced recognition for words produced in Mandarin English compared to Australian English. Infants with live exposure to an Australian talker were not similarly facilitated, perhaps due to the lower vocabulary scores of the infants assigned to the Australian exposure condition. Thus, live exposure can facilitate accent adaptation, but this ability is fragile in young infants and is likely influenced by vocabulary size and the specific mapping between the speaker and the listener's phonological system.

Recursive NPs are difficult to produce and late to emerge. We compare prosodic and syntactic abilities in Japanese-speaking five- and six-year-olds (n = 28) and adults (n = 10). It is reported that syntactic structure in Japanese is prosodically marked via downstep and metrical boost. Results of an elicited imitation task suggested that children had acquired the lexical prosody (contrast between accented and unaccented words), a pre-requisite for downstep realization. While downstep, the prosodic phrasing involved in the complex NPs in this study, was established, children showed interspeaker variation with the metrical boost, a feature that distinguishes recursively embedded NPs from non-recursive NPs. However, variability was also found in adults, indicating that, in contrast to previous results, prosodic encoding of syntax is generally unreliable in adult speech. Finally, the magnitude of metrical boost was not correlated to children's ability to produce recursive possessives, suggesting that prosody does not help bootstrap Japanese children's recursive phrases.

Researchers agree that early literacy activities, like book sharing and parent-child play, are important for stimulating language development. We hypothesize that book sharing is most powerful because it elicits more interactive talk in young children than other activities. Parents of 43 infants (9–18 months) made two daylong audio recordings using the LENA system. We compared a typical day, with spontaneous occurring activities, with an instructed day when caregivers were prompted to do book reading and toy play. Book sharing resulted in a combination of more parent talk, child talk, and interactions than other language activities. Research context did not influence outcomes: no differences were found in language use between the spontaneous and the instructed activities. Overall it seems clear that even with infants shared reading is a strong unique stimulator of language use from parent and child.

Young children simplify word initial consonant clusters by omitting or substituting one (or both) of the elements. Vocalic insertion, coalescence and metathesis are said to be used more seldom (McLeod, van Doorn & Reed, 2001). Data from Norwegian children, however, have shown vocalic insertion to be more frequently used (Simonsen, 1990; Simonsen, Garmann & Kristoffersen, 2019). To investigate the extent to which children use this strategy to differing degrees depending on the ambient language, we analysed word initial cluster production acoustically in nine Norwegian and nine English speaking children aged 2;6–6 years, and eight adults, four from each language. The results showed that Norwegian-speaking children produce significantly more instances of vocalic insertions than English-speaking children do. The same pattern is found in Norwegian- versus English-speaking adults. We argue that this cross-linguistic difference is an example of the influence of prosodic-phonetic biases in language-specific developmental paths in the acquisition of speech.

The present study investigates the production and comprehension of indefinite and definite articles as markers of givenness by typically-developing German-speaking children, from the perspective of information structure theory. The study involves 93 typically-developing children aged four to seven years old with normal language-skills and 20 adults. The results of a story-narration task and a truth-value judgment task reveal that children have more problems with new than with given referents in production as well as comprehension suggesting a “given better than new”-pattern. These findings are explained in the context of perspective-taking capacities and cue weighting theory.

Children with ASD and an IQ-matched control group of typically developing (TD) children completed an elicited-production task which encouraged the production of reversible passive sentences (e.g., “Bob was hit by Wendy”). Although the two groups showed similar levels of correct production, the ASD group produced a significantly greater number of “reversal” errors (e.g., “Wendy was hit by Bob”, when, in fact Wendy hit Bob) than the TD group (who, when they did not produce correct passives, instead generally produced semantically appropriate actives; e.g., “Wendy hit Bob”). These findings suggest that the more formal elements of syntax are spared relative to more semantic/pragmatic/narrative aspects (e.g., manipulating thematic roles) in at least high-functioning children with ASD.

Linguistic expressions of locative spatial relations in sign languages are mostly visually motivated representations of space involving mapping of entities and spatial relations between them onto the hands and the signing space. These are also morphologically complex forms. It is debated whether modality-specific aspects of spatial expressions modulate spatial language development differently in signing compared to speaking children. In a picture description task, we compared the use of locative expressions for containment, support, and occlusion relations by deaf children acquiring Turkish Sign Language and hearing children acquiring Turkish (age 3;5–9;11). Unlike previous reports suggesting a boosting effect of iconicity, and/or a hindering effect of morphological complexity of the locative forms in sign languages, our results show similar developmental patterns for signing and speaking children's acquisition of these forms. Our results suggest the primacy of cognitive development guiding the acquisition of locative expressions by speaking and signing children.

Agreement is a morphosyntactic dependency which is sensitive to the hierarchical structure of the clause and is constrained by the structural distance that separates the elements involved in this relation. In this paper we present two experiments, providing new evidence that Italian-speaking children with Developmental Language Disorder (DLD), as well as Typically Developing (TD) children, are sensitive to the same hierarchical and locality factors that characterise agreement in adult grammars. This sensitivity holds even though DLD children show accrued difficulties in more complex agreement configurations. In the first experiment, a forced-choice task was used to establish whether children are more affected in the computation of S-V agreement when an element intervenes hierarchically or linearly in the agreement relation: DLD children are more subject to attraction errors when the attractor intervenes hierarchically, indicating that DLD children discriminate between hierarchical and linear configurations. The second experiment, also conducted through a forced-choice task, shows that the computation of agreement in DLD children is more ‘fragile’ than in TD children (and also in children with a primary impairment in the phonological domain), in that it is more sensitive to the factors of complexity identified in Moscati and Rizzi's (2014) typology of agreement configurations. To capture the agreement pattern found in DLD children, we put forth a novel hypothesis: the Fragile Computation of Agreement Hypothesis. Its main tenet is that DLD children make use of the same grammatical operations employed by their peers, as demonstrated in Experiment 1, but difficulties increase as a function of the complexity of the agreement configuration.

This study investigates the pitch properties of infant-directed speech (IDS) specific to word-learning contexts in which mothers introduce unfamiliar words to children. Using a semi-spontaneous story-book telling task, we examined (1) whether mothers made distinctions between unfamiliar and familiar words with pitch in IDS compared to adult-directed speech (ADS); (2) whether pitch properties change when mothers address children from 18 to 24 months; and (3) how Mandarin Chinese and Dutch IDS differ in their pitch properties in word-learning contexts. Results show that the mean pitch of Mandarin Chinese IDS was already ADS-like when children were 24 months, but Dutch IDS remained exaggerated in pitch at the same age. Crucially, Mandarin Chinese mothers used a higher pitch and a larger pitch range in IDS when introducing unfamiliar words, while Dutch mothers used a higher pitch specifically for familiar words. These findings contribute to the language-specificity of prosodic input in early lexical development.

We investigated whether Tagalog-speaking children incrementally interpret the first noun as the agent, even if verbal and nominal markers for assigning thematic roles are given early in Tagalog sentences. We asked five- and seven-year-old children and adult controls to select which of two pictures of reversible actions matched the sentence they heard, while their looks to the pictures were tracked. Accuracy and eye-tracking data showed that agent-initial sentences were easier to comprehend than patient-initial sentences, but the effect of word order was modulated by voice. Moreover, our eye-tracking data provided evidence that, by the first noun phrase, seven-year-old children looked more to the target in the agent-initial compared to the patient-initial conditions, but this word order advantage was no longer observed by the second noun phrase. The findings support language processing and acquisition models which emphasize the role of frequency in developing heuristic strategies (e.g., Chang, Dell, & Bock, 2006).

Decontextualized talk is assumed to be used only rarely when children are younger than 30 months. Motivated by Bühler's (1934/1999) linguistic theory that describes different dimensions of (de-)contextualization, we provide evidence that this kind of input can already be found in caregivers’ talking to their 12-month-old children. Such early input is characterized by being decontextualized on some dimensions while being grounded in the immediate context on others. In this way, parents may scaffold understanding of talk about the there-and-then. We also examined whether caregivers adapt decontextualized verbal input to individual trajectories in language development. We observed 59 parent–child interactions within a decorated room when children were 12 months old, and assessed the children's linguistic development at 12 and 24 months of age. However, we did not find differences in the input directed toward children with different trajectories in language development.

This study examined the quantity and quality of parental linguistic input to toddlers with moderate hearing loss (MHL) compared with toddlers with normal hearing (NH). The linguistic input to eighteen toddlers with MHL and twenty-four toddlers with NH was examined during a 10-minute free-play activity in their home environment. Results showed that toddlers with MHL were exposed to an equivalent amount of parental linguistic input compared to toddlers with NH. However, parents of toddlers with MHL used less high-level facilitative language techniques, used less mental state language, and used shorter utterances than parents of toddlers with NH. Quantity and quality measures of parental linguistic input were positively related to the expressive language abilities of toddlers with MHL.

The aim of this study was to examine (a) the development of vocabulary and grammar in children with family-risk (FR) of dyslexia and their peers with no such risk (NoFR) between ages 1;6 and 6;0, and (b) whether FR-status exerted an effect on the direction of temporal relationships between these two constructs. Groups were assessed at seven time-points using standardised tests and parental reports. Results indicated that although FR and NoFR children had a similar development in the earlier years, the FR group appeared to perform significantly more poorly on vocabulary at the end of the preschool period. Results showed no significant effect of FR status on the cross-lagged relations between lexical and grammatical skills, suggesting a similar developmental pattern of cross-domain relations in both groups. However, FR status seemed to have a significantly negative association with vocabulary and grammar scores at age 6;0, resulting in language outcomes in favour of NoFR children.