Background TV and infant-family interactions: Insights from home observations.

Background television has been found to negatively impact children's language development and self-regulatory skills, possibly due to decreased parent-child interactions. Most of the research on the relationship between background TV and caregiver-child interactions has been conducted in laboratory settings. In the current study, we conducted home observations and investigated whether infants engage in fewer interactions with family members in homes where background TV is more prevalent. We observed 32 infants at the ages of 8, 10, and 18 months in their home environments, coding for dyadic interactions (e.g., parent talking to and/or engaging with the child), triadic interactions (e.g., parent and infant play with a toy together), and infants' individual activities. Our findings revealed that background TV was negatively associated with the time infants spent in triadic interactions, positively associated with time spent engaging in individual activities, and not significantly related to the time spent in dyadic interactions. Apart from the relationship between background TV and individual activity time at 8 months, these associations remained significant even after accounting for families' socioeconomic status. These findings imply a correlation between background TV exposure and caregiver-infant-object interactions, warranting a longitudinal analysis with larger sample sizes.

Relation of infants' and mothers' pointing to infants' vocabulary measured directly and with parental reports.

Infants' and parents' pointing gestures predict infants' concurrent and prospective language development. Most studies have measured vocabulary size using parental reports. However, parents tend to underestimate or overestimate infants' vocabulary necessitating the use of direct measures alongside parent reports. The present study examined whether mothers' index-finger pointing, and infants' whole-hand and index-finger pointing at 14 months associate with infants' receptive and expressive vocabulary based on parental reports and directly measured lexical processing efficiency (LPE) concurrently at 14 months and prospectively at 18 months. We used the decorated room paradigm to measure pointing frequency, the Turkish communicative development inventory I to measure infants' receptive vocabulary, Turkish communicative development inventory II to measure their expressive vocabulary, and the Looking-While-Listening (LWL) task to measure LPE. At 14 months, 34 mother-infant dyads, and at 18 months, 30 dyads were included in the analyses. We found that only infants' index-finger pointing frequency at 14 months predicted their LPE (both reaction time and accuracy) prospectively at 18 months but not concurrently at 14 months. Neither maternal pointing nor infants' pointing predicted their receptive and expressive vocabulary based on indirect measurement. The results extend the evidence on the relation between index-finger pointing and language development to a more direct measure of vocabulary.

Correlates of infant pointing frequency in the first year.

This study examines the emergence of concurrent correlates of infant pointing frequency with the aim of contributing to its ontogenetic theories. We measured monthly from 8 to 12 months infants' (N = 56) index-finger pointing frequency along with several candidate correlates: (1) family socioeconomic status (SES), (2) mothers' pointing production, and (3) infants' point following to targets in front of and behind them. Results revealed that (1) infants increased their pointing frequency across age, but high-SES infants had a steeper increase, and a higher pointing frequency than low-SES infants from 10 months onward, (2) maternal pointing frequency was not associated with infant pointing frequency at any age, (3) infants' point following abilities to targets behind their visual fields was positively associated with their pointing frequency at 12 months, after pointing had already emerged around 10 months. Findings suggest that family SES impacts infants' pointing development more generally, not just through maternal pointing. The association between pointing and following points to targets behind, but not in front, suggests that a higher level of referential understanding emerges after, and perhaps through the production of pointing.

Malleability of spatial skills: bridging developmental psychology and toy design for joyful STEAM development.

Previous research has established that advances in spatial cognition predict STEAM success, and construction toys provide ample opportunities to foster spatial cognition. Despite various construction toy designs in the market, mostly brick-shaped building blocks are used in spatial cognition research. This group of toys is known to enhance mental rotation; however, mental rotation is not the only way to comprehend the environment three-dimensionally. More specifically, mental folding and perspective taking training have not received enough attention as they can also be enhanced with the construction toys, which are framed based on the 2×2 classification of spatial skills (intrinsic-static, intrinsic-dynamic, extrinsic-static, extrinsic-dynamic). To address these gaps, we compile evidence from both developmental psychology and toy design fields to show the central role played by mental folding and perspective taking skills as well as the importance of the variety in toy designs. The review was conducted systematically by searching peer reviewed design and psychology journals and conference proceedings. We suggest that, over and above their physical properties, construction toys offer affordances to elicit spatial language, gesture, and narrative among child-caregiver dyads. These interactions are essential for the development of spatial skills in both children and their caregivers. As developmental psychology and toy design fields are two domains that can contribute to the purpose of developing construction toys to boost spatial skills, we put forward six recommendations to bridge the current gaps between these fields. Consequently, new toy designs and empirical evidence regarding malleability of different spatial skills can contribute to the informal STEAM development.

Children's associations between space and pitch are differentially shaped by language.

Musical properties, such as auditory pitch, are not expressed in the same way across cultures. In some languages, pitch is expressed in terms of spatial height (high vs. low), whereas others rely on thickness vocabulary (thick = low frequency vs. thin = high frequency). We investigated how children represent pitch in the face of this variable linguistic input by examining the developmental trajectory of linguistic and non-linguistic space-pitch associations in children who acquire Dutch (a height-pitch language) or Turkish (a thickness-pitch language). Five-year-olds, 7-year-olds, 9-year-olds, and 11-year-olds were tested for their understanding of pitch terminology and their associations of spatial dimensions with auditory pitch when no language was used. Across tasks, thickness-pitch associations were more robust than height-pitch associations. This was true for Turkish children, and also Dutch children not exposed to thickness-pitch vocabulary. Height-pitch associations, on the other hand, were not reliable-not even in Dutch-speaking children until age 11-the age when they demonstrated full comprehension of height-pitch terminology. Moreover, Turkish-speaking children reversed height-pitch associations. Taken together, these findings suggest thickness-pitch associations are acquired in similar ways by children from different cultures, but the acquisition of height-pitch associations is more susceptible to linguistic input. Overall, then, despite cross-cultural stability in some components, there is variation in how children come to represent musical pitch, one of the building blocks of music. RESEARCH HIGHLIGHTS: Children from diverse cultures differ in their understanding of music vocabulary and in their nonlinguistic associations between spatial dimensions and auditory pitch. Height-pitch mappings are acquired late and require additional scaffolding from language, whereas thickness-pitch mappings are acquired early and are less susceptible to language input. Space-pitch mappings are not static from birth to adulthood, but change over development, suggesting music cognition is shaped by cross-cultural experience.

Gradual Route to Productivity: Evidence from Turkish Morphological Causatives.

Becoming productive with grammatical categories is a gradual process in children's language development. Here, we investigated this transition process by focusing on Turkish causatives. Previous research examining spontaneous and elicited production of Turkish causatives with familiar verbs attested the onset and early stages of productivity at ages 2 to 3 (Aksu-Koç & Slobin, 1985; Nakipoglu, Uzundag, & Sarigül, 2021). So far, however, we know very little about children's understanding of causatives with novel verbs. In the present study, we asked: (a) When does the generalization of causative morphology in a novel context emerge? and (b) What role does child-directed input play in this development? To answer the first question, we conducted comprehension-judgment experiments with children aged 2;6-6;11 using pseudo-verbs (Study 1 & 2). Results showed that children preferred the Turkish causative suffix -DIr over an unrelated or no suffix to denote caused events earliest at age 4;10. To answer the second question, we analyzed child-directed speech from a longitudinal corpus of Turkish language acquisition (Study 3). Results showed that when addressing children younger than age 3, caregivers used the -DIr suffix with little variation considering the overall variability of verbs they could utter. Overall, these findings suggest that productivity with morphological causatives in a novel context emerges in a later stage of acquisition. This later development might partly be accounted for by the insufficient variation of morphological causatives in the early input.

Detecting structured repetition in child-surrounding speech: Evidence from maximally diverse languages.

Caretakers tend to repeat themselves when speaking to children, either to clarify their message or to redirect wandering attention. This repetition also appears to support language learning. For example, words that are heard more frequently tend to be produced earlier by young children. However, pure repetition only goes so far; some variation between utterances is necessary to support acquisition of a fully productive grammar. When individual words or morphemes are repeated, but embedded in different lexical and syntactic contexts, the child has more information about how these forms may be used and combined. Corpus analysis has shown that these partial repetitions frequently occur in clusters, which have been coined variation sets. More recent research has introduced algorithms that can extract these variation sets automatically from corpora with the goal of measuring their relative prevalence across ages and languages. Longitudinal analyses have revealed that rates of variation sets tend to decrease as children get older. We extend this research in several ways. First, we consider a maximally diverse sample of languages, both genealogically and geographically, to test the generalizability of developmental trends. Second, we compare multiple levels of repetition, both words and morphemes, to account for typological differences in how information is encoded. Third, we consider several additional measures of development to account for deficiencies in age as a measure of linguistic aptitude. Fourth, we examine whether the levels of repetition found in child-surrounding speech is greater or less than what would have been expected by chance. This analysis produced a new measure, redundancy, which captures how repetitive speech is on average given how repeititive it could have been. Fifth, we compare rates of repetition in child-surrounding and adult-directed speech to test whether variation sets are especially prevalent in child-surrounding speech. We find that (1) some languages show increases in repetition over development, (2) true estimates of variation sets are generally lower than or equal to random baselines, (3) these patterns are largely convergent across developmental indices, and (4) adult-directed speech is reliably less redundant, though in some cases more repetitive, than child-surrounding speech. These results are discussed with respect to features of the corpora, typological properties of the languages, and differential rates of change in repetition and redundancy over children's development.

German-speaking children use sentence-initial case marking for predictive language processing at age four.

Adults incrementally integrate multiple sources of information to predict the upcoming linguistic structure. Although we have substantial evidence that children can use lexicosemantic information triggered by the verb, we have limited information as to whether children can use morphosyntax to generate predictions during the course of processing. Previous studies show that four-year-old Turkish-speaking children can use case-marking cues predictively; however German-speaking children have been reported to fail until late in development. The present visual-world eye-tracking study provides the first evidence from four-year-old German-speaking children (mean age: 4;03) interpreting sentence initial case marking cues independent of the identity of the verb and the canonical word order to predict the thematic role of the upcoming argument. We presented children with a visual context with a stereotypical but ambiguous event, the thematic structure of which can be resolved only on the basis of the case marking cues on subject-initial and object-initial structures locating the verb sentence-finally. Children were able to use the accusative case on the non-canonical object-initial utterances to predict that the upcoming argument should have the agent role before this argument and the verb became available. This study shows that the previously reported discrepancy between these two case-marking languages (i.e., Turkish and German) is not due to the crosslinguistic differences but due to methodological differences employed across studies. These findings provide support for language acquisition theories assuming early abstractions and adult-like parsing mechanisms predictively integrating multiple sources of cues.

When Even a Robot Tutor Zooms: A Study of Embodiment, Attitudes, and Impressions.

This study used an online second language (L2) vocabulary lesson to evaluate whether the physical body (i.e., embodiment) of a robot tutor has an impact on how the learner learns from the robot. In addition, we tested how individual differences in attitudes toward robots, first impressions of the robot, anxiety in learning L2, and personality traits may be related to L2 vocabulary learning. One hundred Turkish-speaking young adults were taught eight English words in a one-on-one Zoom session either with a NAO robot tutor (N = 50) or with a voice-only tutor (N = 50). The findings showed that participants learned the vocabulary equally well from the robot and voice tutors, indicating that the physical embodiment of the robot did not change learning gains in a short vocabulary lesson. Further, negative attitudes toward robots had negative effects on learning for participants in the robot tutor condition, but first impressions did not predict vocabulary learning in either of the two conditions. L2 anxiety, on the other hand, negatively predicted learning outcomes in both conditions. We also report that attitudes toward robots and the impressions of the robot tutor remained unchanged before and after the lesson. As one of the first to examine the effectiveness of robots as an online lecturer, this study presents an example of comparable learning outcomes regardless of physical embodiment.

Influence of causal language on causal understanding: A comparison between Swiss German and Turkish.

Young children have difficulties in understanding untypical causal relations. Although we know that hearing a causal description facilitates this understanding, less is known about what particular features of causal language are responsible for this facilitation. Here, we asked two questions. First, do syntactic and morphological cues in the grammatical structure of sentences facilitate the extraction of causal meaning? Second, do these different cues influence this facilitation to different degrees? We studied children learning either Swiss German or Turkish, two languages that differ in their expression of causality. Swiss German predominantly uses lexical causatives (e.g., schniidä [cut]), which lack a formal marker to denote causality. Turkish, alongside lexical causatives, uses morphological causatives, which formally mark causation (e.g., ye [eat] vs. yeDIr [feed]). We tested 2.5- to 3.5-year-old children's understanding of untypical cause-effect relations described with either noncausal language (e.g., Here is a cube and a car) or causal language using a pseudo-verb (e.g., lexical: The cube gorps the car). We tested 135 Turkish-learning children (noncausal, lexical, and morphological conditions) and 90 Swiss-German-learning children (noncausal and lexical conditions). Children in both language groups performed better in the causal language condition(s) than in the noncausal language condition. Furthermore, Turkish-learning children's performance in both the lexical and morphological conditions was similar to that of Swiss-German-learning children in the lexical condition and did not differ from each other. These findings suggest that the structural cues of causal language support children's understanding of untypical causal relations regardless of the type of construction.

Number and type of toys affect joint attention of mothers and infants.

Establishing joint attention with a caregiver on a physical object provides an optimal environment for language learning for infants. In the present study, we investigated whether 12-month-olds and their mothers establish higher quality joint attention interactions in the presence of fewer compared to more toys. As a secondary goal, we investigated how different types of toys affect how mother-infant dyads establish joint attention. In a five-minute free play setting, mothers and infants participated in either Five Toy (n = 48) or Twelve Toy (n = 33) groups. They were given organizational (i.e., toys that require arrangement of parts), responsive (i.e., toys that emit sounds via manipulation), and symbolic toys (i.e., toys that elicit pretend play). Results showed that compared to the Twelve Toy group, joint attention interactions in the Five Toy group were less frequent, lasted longer, were more likely to be initiated by maternal following than by maternal directing of infants' attention, and more likely to be coordinated in which infants demonstrated awareness of the mothers' simultaneous attentional focus by looking at their mothers, vocalizing, or turn-taking. We further found longer joint attention durations on organizational compared to symbolic toys, which were preferred to a lesser extent by the dyads. With responsive toys, mothers were more likely to initiate joint attention by following their infants' attention. Joint attention interactions lasted longer and were more likely to be coordinated in the second half compared to the first half of the play session, suggesting that over time it became easier for the mothers and infants to settle on certain toys for more elaborate play. In sum, mothers and infants establish higher-quality joint attention with fewer toys in general and with organizational toys in particular.

Space-pitch associations differ in their susceptibility to language.

To what extent are links between musical pitch and space universal, and to what extent are they shaped by language? There is contradictory evidence in support of both universality and linguistic relativity presently, leaving the question open. To address this, speakers of Dutch who talk about pitch in terms of spatial height and speakers of Turkish who use a thickness metaphor were tested in simple nonlinguistic space-pitch association tasks. Both groups showed evidence of a thickness-pitch association, but differed significantly in their height-pitch associations, suggesting the latter may be more susceptible to language. When participants had to match pitches to spatial stimuli where height and thickness were opposed (i.e., a thick line high in space vs. a thin line low in space), Dutch and Turkish differed in their relative preferences. Whereas Turkish participants predominantly opted for a thickness-pitch interpretation-even if this meant a reversal of height-pitch mappings-Dutch participants favored a height-pitch interpretation more often. These findings provide new evidence that speakers of different languages vary in their space-pitch associations, while at the same time showing such associations are not equally susceptible to linguistic influences. Some space-pitch (i.e., height-pitch) associations are more malleable than others (i.e., thickness-pitch).

Children's reliance on the non-verbal cues of a robot versus a human.

Robots are used for language tutoring increasingly often, and commonly programmed to display non-verbal communicative cues such as eye gaze and pointing during robot-child interactions. With a human speaker, children rely more strongly on non-verbal cues (pointing) than on verbal cues (labeling) if these cues are in conflict. However, we do not know how children weigh the non-verbal cues of a robot. Here, we assessed whether four- to six-year-old children (i) differed in their weighing of non-verbal cues (pointing, eye gaze) and verbal cues provided by a robot versus a human; (ii) weighed non-verbal cues differently depending on whether these contrasted with a novel or familiar label; and (iii) relied differently on a robot's non-verbal cues depending on the degree to which they attributed human-like properties to the robot. The results showed that children generally followed pointing over labeling, in line with earlier research. Children did not rely more strongly on the non-verbal cues of a robot versus those of a human. Regarding pointing, children who perceived the robot as more human-like relied on pointing more strongly when it contrasted with a novel label versus a familiar label, but children who perceived the robot as less human-like did not show this difference. Regarding eye gaze, children relied more strongly on the gaze cue when it contrasted with a novel versus a familiar label, and no effect of anthropomorphism was found. Taken together, these results show no difference in the degree to which children rely on non-verbal cues of a robot versus those of a human and provide preliminary evidence that differences in anthropomorphism may interact with children's reliance on a robot's non-verbal behaviors.

The acquisition and use of relative clauses in Turkish-learning children's conversational interactions: a cross-linguistic approach.

Using a cross-linguistic approach, we investigated Turkish-speaking children's acquisition and use of relative clauses (RCs) by examining longitudinal child-caregiver interactions and cross-sectional peer conversations. Longitudinal data were collected from 8 children between the ages of 8 and 36 months. Peer conversational corpus came from 78 children aged between 43 and 64 months. Children produced RCs later than in English (Diessel, 2004) and Mandarin (Chen & Shirai, 2015), and demonstrated increasing semantic and structural complexity with age. Despite the morphosyntactic difficulty of object RCs, and prior experimental findings showing a subject RC advantage, preschool-aged children produced object RCs, which were highly frequent in child-directed speech, as frequently as subject RCs. Object RCs in spontaneous speech were semantically less demanding (with pronominal subjects and inanimate head nouns) than the stimuli used in prior experiments. Results suggest that multiple factors such as input frequency and morphosyntactic and semantic difficulty affect the acquisition patterns.

Verb-based prediction during language processing: the case of Dutch and Turkish.

This study investigated whether cross-linguistic differences affect semantic prediction. We assessed this by looking at two languages, Dutch and Turkish, that differ in word order and thus vary in how words come together to create sentence meaning. In an eye-tracking task, Dutch and Turkish four-year-olds (N = 40), five-year-olds (N = 58), and adults (N = 40) were presented with a visual display containing two familiar objects (e.g., a cake and a tree). Participants heard semantically constraining (e.g., "The boy eats the big cake") or neutral sentences (e.g., "The boy sees the big cake") in their native language. The Dutch data revealed a prediction effect for children and adults; however, it was larger for the adults. The Turkish data revealed no prediction effect for the children but only for the adults. These findings reveal that experience with word order structures and/or automatization of language processing routines may lead to timecourse differences in semantic prediction.

Why wait for the verb? Turkish speaking children use case markers for incremental language comprehension.

During language comprehension we must rapidly determine the thematic roles of arguments (who did what to whom) in order to semantically integrate the players into a single event and predict upcoming structure. While some languages signal these relations mostly with reliable word order, others rely more on case markers. The present study explores whether Turkish-speaking children use case marking predictively during online language comprehension. Specifically, we use the visual-world paradigm to test whether 4-year-olds (and adults) can use a contrast between nominative and accusative case on the first noun to predict the referent of the second noun in verb-medial and verb-final spoken sentences. In verb-medial sentences, both children and adults used case to predict the upcoming noun, but children did so only after hearing the verb. In verb-final structures, however, both children and adults made predictive looks to the correct referent prior to the second noun (and the verb). Thus, Turkish-speaking preschoolers interpret case marking incrementally, independent of the verb, and use it to anticipate the upcoming argument. These findings are inconsistent with the hypothesis that the online interpretation of case marking depends on a late maturing neural circuit. The predictive use of case at four provides strong evidence that children's comprehension relies on broad, abstract mappings between syntax and semantics, which allow children to determine the event role of a case marked argument prior to identifying the verb.

A universal cue for grammatical categories in the input to children: Frequent frames.

How does a child map words to grammatical categories when words are not overtly marked either lexically or prosodically? Recent language acquisition theories have proposed that distributional information encoded in sequences of words or morphemes might play a central role in forming grammatical classes. To test this proposal, we analyze child-directed speech from seven typologically diverse languages to simulate maximum variation in the structures of the world's languages. We ask whether the input to children contains cues for assigning syntactic categories in frequent frames, which are frequently occurring nonadjacent sequences of words or morphemes. In accord with aggregated results from previous studies on individual languages, we find that frequent word frames do not provide a robust distributional pattern for accurately predicting grammatical categories. However, our results show that frames are extremely accurate cues cross-linguistically at the morpheme level. We theorize that the nonadjacent dependency pattern captured by frequent frames is a universal anchor point for learners on the morphological level to detect and categorize grammatical categories. Whether frames also play a role on higher linguistic levels such as words is determined by grammatical features of the individual language.

Children's referential communication skills: The role of cognitive abilities and adult models of speech.

Referential communication is effective when speakers describe a specific entity in a way that leads to accurate identification of that referent among competitors. Young children's initial referential expressions are often inadequate, and this state of miscommunication needs to be repaired in subsequent communicative attempts. Exposure to adults' effective descriptions of referents is beneficial for children to develop referentially clear initial descriptions. Here, we examined whether adult models of speech also provide benefits for children's communicative repair behavior. Furthermore, we assessed the relation between children's cognitive abilities and referential communication skills. We tested 59 children (aged 4 years to 5 years 9 months) on their ability to request specific stickers among similar distractors in a pretest-modeling-posttest design. In the modeling phase, 30 children heard more informative descriptions of stickers with relative clauses (e.g., "you selected the horse that the boy is riding") and 29 children heard less informative descriptions with demonstrative noun phrases (e.g., "you selected that horse"). In a second session, we measured children's short-term memory, executive functions (working memory and cognitive flexibility), and theory of mind. Children who heard more informative expressions showed a greater increase in uniquely identifying initial descriptions than children who heard less informative expressions. Hearing more informative expressions did not provide an additional benefit in repairing ambiguous messages, an ability we found to be related to cognitive flexibility and memory. Results indicate that informative language structures that uniquely identify referents provide limited benefits to children for effective communication where children's short-term memory and executive functions also matter.