Sentence-final completion norms for 2925 Mexican Spanish sentence contexts.

Sentence-final completion tasks serve as valuable tools in studying language processing and the associated predictive mechanisms. There are several established sentence-completion norms for languages like English, Portuguese, French, and Spanish, each tailored to the language it was designed for and evaluated in. Yet, cultural variations among native speakers of the same language complicate the claim of a universal application of these norms. In this study, we developed a corpus of 2925 sentence-completion norms specifically for Mexican Spanish. This corpus is distinctive for several reasons: Firstly, it is the most comprehensive set of sentence-completion norms for Mexican Spanish to date. Secondly, it offers a substantial range of experimental stimuli with considerable variability in terms of the predictability of word sentence completion (cloze probability/surprisal) and the level of uncertainty inherent in the sentence context (entropy). Thirdly, the syntactic complexity of the sentences in the corpus is varied, as are the characteristics of the final word nouns (including aspects of concreteness/abstractness, length, and frequency). This paper details the generation of the sentence contexts, explains the methodology employed for data collection from a total of 1470 participants, and outlines the approach to data analysis for the establishment of sentence-completion norms. These norms provide a significant contribution to fields such as linguistics, cognitive science, and machine learning, among others, by enhancing our understanding of language, predictive mechanisms, knowledge representation, and context representation. The collected data is accessible through the Open Science Framework (OSF) at the following link: https://osf.io/js359/?view_only=bb1b328d37d643df903ed69bb2405ac0 .

Validation of an open source, remote web-based eye-tracking method (WebGazer) for research in early childhood.

Measuring eye movements remotely via the participant's webcam promises to be an attractive methodological addition to in-person eye-tracking in the lab. However, there is a lack of systematic research comparing remote web-based eye-tracking with in-lab eye-tracking in young children. We report a multi-lab study that compared these two measures in an anticipatory looking task with toddlers using WebGazer.js and jsPsych. Results of our remotely tested sample of 18-27-month-old toddlers (N = 125) revealed that web-based eye-tracking successfully captured goal-based action predictions, although the proportion of the goal-directed anticipatory looking was lower compared to the in-lab sample (N = 70). As expected, attrition rate was substantially higher in the web-based (42%) than the in-lab sample (10%). Excluding trials based on visual inspection of the match of time-locked gaze coordinates and the participant's webcam video overlayed on the stimuli was an important preprocessing step to reduce noise in the data. We discuss the use of this remote web-based method in comparison with other current methodological innovations. Our study demonstrates that remote web-based eye-tracking can be a useful tool for testing toddlers, facilitating recruitment of larger and more diverse samples; a caveat to consider is the larger drop-out rate.

The role of imageability in noun and verb acquisition in children with Down syndrome and their peers with typical development.

Our main objective was to analyze the role of imageability in relation to the age of acquisition (AoA) of nouns and verbs in Spanish-speaking children with Down syndrome (DS) and their peers with typical development (TD). The AoA of nouns and verbs was determined using the MacArthur-Bates CDIs adapted to the profile of children with DS. The AoA was analyzed using a linear mixed-effect model, including factors of imageability, group, and word class, and controlling for word frequency and word length. This analysis showed that high imaginable and short words were acquired early. Children with DS acquired the words later than TD peers. An interaction between imageability and group indicated that the effect of imageability was greater in the DS group. We discuss this effect considering DS children's phonological memory difficulties. The overall results confirm the role that imageability and word length play in lexical acquisition, an effect that goes beyond word class.

Cross-cultural adaptation of the everyday cognition scale (M-ECog) in older Mexican adults with cognitive impairment.

The Everyday Cognition (ECog) scale was created to evaluate the functional abilities of older adults across a wide range of abilities between normal aging and dementia. ECog screens cognitive alterations such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI). This early recognition is done by the measurement of the ability to perform the activities of daily living (ADLs). Objective: To establish the cross-cultural adaptation, validity, and reliability of the ECog Mexican version (M-ECog) in participants with: SCD, MCI, and dementia coming from a memory clinic. Methods: There were 200 patients and their respective informants in a memory clinic of a third level hospital in Mexico City. Four groups were studied: 50 cognitively healthy (CH), 50 SCD, 50 MCI, and 50 dementia. The clinical evaluation included: sociodemographic and health characteristics, cognitive status by the Mini-Mental State Evaluation (MMSE) and Montreal Cognitive Evaluation Spanish version (MoCA-E), and caregiver information (informants) about the difficulty in ADLs as well as the ECog Spanish version (M-ECog). Results: The M-ECog was significantly correlated with MMSE, MoCA-E, and ADLs. It showed the ability to discriminate the different cognitive declines (Cronbach's alpha 0.881). The intra-class correlation coefficient was 0.877 (95% confidence interval - CI, 0.850-0.902; p<0.001). The patient's group area under curve (AUC) of M-ECog for SCD was 0.70 (95%CI 0.58-0.82, p<0.005), for MCI it was 0.94 (95%CI 0.89-0.99, p<0.001) and for dementia 0.86 (95%CI 0.79-0.92, p<0.001). Conclusion: The M-ECog scale proves to be valid and reliable for measuring everyday abilities mediated by cognition. It is self-applicable without requiring extensive prior formation. It is useful to screen for SCD and MCI in older Mexican adults.

A escala Cognição Cotidiana (ECog) foi criada para avaliar as habilidades funcionais de idosos em uma ampla gama de habilidades entre o envelhecimento normal e a demência. O ECog rastreia alterações cognitivas como declínio cognitivo subjetivo (DCS) e comprometimento cognitivo leve (CCL). Esse reconhecimento precoce é feito pela mensuração da capacidade de realizar as atividades de vida diária (AVD). Objetivo: Estabelecer a adaptação transcultural, validade e confiabilidade da versão mexicana do ECog (M-ECog) em participantes com: SCD, MCI e demência provenientes de uma clínica de memória. Métodos: Foram 200 pacientes e seus respectivos informantes em uma clínica de memória de um hospital de terceiro nível na Cidade do México. Quatro grupos foram estudados: 50 cognitivamente saudáveis (CH), 50 SCD, 50 MCI e 50 com demência. A avaliação clínica incluiu: características sociodemográficas e de saúde, estado cognitivo pelo Mini-Mental State Evaluation (MMSE) e Montreal Cognitive Evaluation versão em espanhol (MoCA-E), bem como informações do cuidador (informantes) sobre a dificuldade nas AVD e o ECog versão em espanhol (M-ECog). Resultados: O M-ECog foi significativamente correlacionado com MMSE, MoCA-E e AVD. Mostrou capacidade de discriminar os diferentes declínios cognitivos (alfa de Cronbach 0,881). O coeficiente de correlação intraclasse foi de 0,877 (intervalo de confiança de 95% ­ IC95%, 0,850­0,902; p<0,001). A AUC do grupo do paciente de M-ECog para SCD foi de 0,70 (IC95% 0,58­0,82, p<0,005), para MCI foi de 0,94 (IC95% 0,89­0,99, p<0,001) e para demência foi de 0,86 (IC95% 0,79­0,92, p<0,001). Conclusão: A escala M-ECog mostra-se válida e confiável para medir habilidades cotidianas mediadas pela cognição. É autoaplicável sem exigir extensa formação prévia. É útil para rastrear MSC e MCI em adultos mexicanos mais velhos.

Cross-cultural adaptation of the everyday cognition scale (M-ECog) in older Mexican adults with cognitive impairment / Adaptação transcultural da escala de cognição cotidiana (M-ECog) em idosos mexicanos com comprometimento cognitivo

Abstract The Everyday Cognition (ECog) scale was created to evaluate the functional abilities of older adults across a wide range of abilities between normal aging and dementia. ECog screens cognitive alterations such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI). This early recognition is done by the measurement of the ability to perform the activities of daily living (ADLs). Objective: To establish the cross-cultural adaptation, validity, and reliability of the ECog Mexican version (M-ECog) in participants with: SCD, MCI, and dementia coming from a memory clinic. Methods: There were 200 patients and their respective informants in a memory clinic of a third level hospital in Mexico City. Four groups were studied: 50 cognitively healthy (CH), 50 SCD, 50 MCI, and 50 dementia. The clinical evaluation included: sociodemographic and health characteristics, cognitive status by the Mini-Mental State Evaluation (MMSE) and Montreal Cognitive Evaluation Spanish version (MoCA-E), and caregiver information (informants) about the difficulty in ADLs as well as the ECog Spanish version (M-ECog). Results: The M-ECog was significantly correlated with MMSE, MoCA-E, and ADLs. It showed the ability to discriminate the different cognitive declines (Cronbach's alpha 0.881). The intra-class correlation coefficient was 0.877 (95% confidence interval — CI, 0.850-0.902; p<0.001). The patient's group area under curve (AUC) of M-ECog for SCD was 0.70 (95%CI 0.58-0.82, p<0.005), for MCI it was 0.94 (95%CI 0.89-0.99, p<0.001) and for dementia 0.86 (95%CI 0.79-0.92, p<0.001). Conclusion: The M-ECog scale proves to be valid and reliable for measuring everyday abilities mediated by cognition. It is self-applicable without requiring extensive prior formation. It is useful to screen for SCD and MCI in older Mexican adults.

RESUMO A escala Cognição Cotidiana (ECog) foi criada para avaliar as habilidades funcionais de idosos em uma ampla gama de habilidades entre o envelhecimento normal e a demência. O ECog rastreia alterações cognitivas como declínio cognitivo subjetivo (DCS) e comprometimento cognitivo leve (CCL). Esse reconhecimento precoce é feito pela mensuração da capacidade de realizar as atividades de vida diária (AVD). Objetivo: Estabelecer a adaptação transcultural, validade e confiabilidade da versão mexicana do ECog (M-ECog) em participantes com: SCD, MCI e demência provenientes de uma clínica de memória. Métodos: Foram 200 pacientes e seus respectivos informantes em uma clínica de memória de um hospital de terceiro nível na Cidade do México. Quatro grupos foram estudados: 50 cognitivamente saudáveis (CH), 50 SCD, 50 MCI e 50 com demência. A avaliação clínica incluiu: características sociodemográficas e de saúde, estado cognitivo pelo Mini-Mental State Evaluation (MMSE) e Montreal Cognitive Evaluation versão em espanhol (MoCA-E), bem como informações do cuidador (informantes) sobre a dificuldade nas AVD e o ECog versão em espanhol (M-ECog). Resultados: O M-ECog foi significativamente correlacionado com MMSE, MoCA-E e AVD. Mostrou capacidade de discriminar os diferentes declínios cognitivos (alfa de Cronbach 0,881). O coeficiente de correlação intraclasse foi de 0,877 (intervalo de confiança de 95% — IC95%, 0,850-0,902; p<0,001). A AUC do grupo do paciente de M-ECog para SCD foi de 0,70 (IC95% 0,58-0,82, p<0,005), para MCI foi de 0,94 (IC95% 0,89-0,99, p<0,001) e para demência foi de 0,86 (IC95% 0,79-0,92, p<0,001). Conclusão: A escala M-ECog mostra-se válida e confiável para medir habilidades cotidianas mediadas pela cognição. É autoaplicável sem exigir extensa formação prévia. É útil para rastrear MSC e MCI em adultos mexicanos mais velhos.

Word prediction using closely and moderately related verbs in Down syndrome.

People with Down syndrome (DS) have several difficulties in language learning, and one of the areas most affected is language production. Theoretical frameworks argue that prediction depends on the production system. Yet, people with DS can predict upcoming nouns using semantically related verbs. Possibly, prediction skills in people with DS are driven by their associative mechanism rather than by the prediction mechanism based on the production system. This study explores prediction mechanisms in people with DS and their relationship with production skills. Three groups were evaluated in a preferential-looking task: young adults, children with DS, and a typically developing control group paired by sex and mental age. Participants saw two images, a target and a distractor. They also heard a sentence in one of the three conditions: with a verb that was closely related to the object (e.g., "The woman read the book"), with a verb that was moderately related to the object (e.g., "My uncle waited for the bus"), or with a verb that was unrelated to the object (e.g., "My sister threw a broom"). Their productive vocabulary was then measured. In the young adult and typically developing groups, the results showed prediction in sentences with highly and moderately related verbs. Participants with DS, however, showed prediction skills only in the highly related context. There was no influence of chronological age, mental age, or production on prediction skills. These results indicate that people with DS base prediction mainly on associative mechanisms and they have difficulty in generating top-down predictions.

Perceptual similarity effect in people with Down syndrome.

Background The perceptual similarity between two objects, specifically similarity in the shape of the referents, is a crucial element for relating words in earlier stages of development. The role of this perceptual similarity has not been systematically explored in children with Down syndrome (DS). Method: The aim was to explore the role of perceptual similarity in relationships between words in children with DS. Two groups, children with typical development (TD) and children with DS, matched by gender and mental age, participated in a priming task with a preferential looking paradigm. The task presented validated perceptually-related word pairs (prime-target) and perceptually unrelated pairs. In the priming task both groups were asked to look at a target image (e.g. ball) that was perceptually related (e.g. cookie) or unrelated (e.g. skirt) to the prime. Results: Participants from both groups looked more at targets without perceptual similarity than at those with similarity to the prime, suggesting an inhibition effect. Conclusions: This finding suggests the role of visual information, particularly the shape of the referents, in the construction of the lexical system.

Maternal education revisited: Vocabulary growth in English and Spanish from 16 to 30 months of age.

This paper reports on a cross-language longitudinal study in which we extend previous research on the effects of maternal education on vocabulary growth in Spanish- and English-dominant children at three time points: 16 months, 22 months, and 30 months of age. This study addresses recent conflicting evidence regarding the role of maternal education in children's acquisition of Spanish. Participants were 62 English-dominant children, 47 Spanish-dominant children, and their mothers. Growth curve models were constructed separately for English and Spanish vocabulary. Strong growth rate reliability and effect sizes were evinced for vocabulary across samples. As expected, in English-dominant children, maternal education predicted English vocabulary and growth from 16 to 30 months of age. However, in Spanish-dominant children, there was no significant effect of maternal education on vocabulary or growth, although there was a descriptive advantage for children of college-educated mothers at 30 months of age. In conjunction with prior evidence, we conclude that the effect of maternal education on maternal input and child vocabulary does not generalize readily to children whose first language is Spanish. Our findings contribute to a literature that suggests that focusing on maternal beliefs, input, and the home literacy environment are more fruitful approaches in the study of children learning Spanish in the U.S. Further, the importance of maternal beliefs highlights the need to support parent investment in the quantity and quality of input in the home language.

Developmental changes in phonological and semantic priming effects in Spanish-speaking toddlers.

Research on the early lexical-semantic system has described how toddlers organize word representations based on semantic and phonological features. This study is a longitudinal investigation of the development of this organization during infancy. Middle-high socioeconomic status Mexican toddlers (n = 28, 15 female) were presented with a preferential looking task using an eye-tracker at 18, 21, and 24 months of age, manipulating semantic and phonological lexical links. The experimental task consisted of presenting an auditory label, which was phonologically or semantically related or unrelated, with a displayed target image. Mean proportion of target looking, time-course of fixations, pupillometry, and vocabulary network analysis were used to describe the properties of priming effects. The results showed that phonological priming developed earlier than semantic priming, and that they were produced by behavioral interference. In addition, pupil dilation showed differential use of cognitive effort in critical developmental periods. Finally, the density of vocabulary networks correlated with semantic effects, and vocabulary size and local network features with phonological effects. These findings extend our understanding of the development of the lexical-semantic system during infancy. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Mediated semantic priming interference in toddlers as seen through pupil dynamics.

Mediated priming refers to the activation of a target word by a prime word through an intermediate word. This type of priming provides behavioral evidence of between- and within-level spreading activation in the lexical system. Studies of toddlers show phonosemantic between-level mediated priming that supports a cascade of activation between different levels of processing. However, it is not clear whether the activation can spread freely within the same level. This study explored whether 24-month-old toddlers show mediated priming effects at the semantic level (e.g., cat [prime] - mouse [mediator] - cheese [target]) with a preferential looking task using an eye tracker. The results show a smaller proportion of target looking and greater pupil size in the related condition than in the unrelated condition; these effects were greater in the second half of the analysis window. We interpret these data as a spreading activation that is partially free but modulated during infancy. We also provide evidence of pupil dilation as a neurophysiological marker in a preferential looking task with priming. We discuss the results in light of the cognitive control, inhibition, and general cognitive skills of toddlers.

A longitudinal study of the role of vocabulary size in priming effects in early childhood.

Studies on lexical development in young children often suggest that the organization of the early lexicon may vary with age and increasing vocabulary size. In the current study, we explicitly examined this suggestion in further detail using a longitudinal study of the development of phonological and semantic priming effects in the same group of toddlers at three different ages. In particular, our longitudinal design allows us to disentangle effects of increasing age and vocabulary size on priming and the extent to which vocabulary size may predict later priming effects. We tested phonological and semantic priming effects in monolingual German infants at 18, 21, and 24 months of age. We used the intermodal preferential looking paradigm combined with eye tracking to measure the influence of phonologically and semantic related/unrelated primes on target recognition. We found that phonological priming effects were predicted by participants' current vocabulary size even after controlling for participants' age and participants' early vocabulary size. Semantic priming effects were, in contrast, not predicted by vocabulary size. Finally, we also found a relationship between early phonological priming effects and later semantic priming effects as well as between early semantic priming effects and later phonological priming effects, potentially suggesting (limited) consistency in lexical structure across development. Taken together, these results highlight the important role of vocabulary size in the development of priming effects in early childhood.

The influence of sleep on language production modalities in preschool children with Down syndrome.

Evidence suggests that sleep may relate to oral language production in children with Down syndrome. However, these children are capable of using complex referential gestures as a compensation strategy for problems with oral production, and those with a greater productive oral vocabulary have less gestural vocabulary. The goal of this study was to explore whether sleep quality relates to oral and gestural production modalities in children with Down syndrome. We evaluated 36 preschool children with and without Down syndrome, paired by chronological age and gender, with similar sociodemographic backgrounds, using actigraphy to measure sleep behaviour and the Communicative Development Inventory for Down syndrome to measure vocabulary. Children with Down syndrome with better sleep efficiency showed more oral production but less gestural production. These results highlight the importance of sleep quality to language learning in children with Down syndrome.

An Exploration of Social Cognition in Children with Different Degrees of Genetic Deletion in Williams Syndrome.

An explanation for the social dysfunction observed in Williams syndrome may be deficits in social cognition. This study explored aspects of social cognition in children with Williams syndrome with different genotypes. The 12 participants included one with a 1.1 Mb deletion that retained the GTF2IRD1, GTF2I, and GTF2IRD2 genes, seven with a 1.5 Mb deletion that preserved the GTF2IRD2 gene, and four with a 1.8 Mb deletion with loss of all three genes. The participant retaining all three genes was found to have better performance on social judgment and first-order theory of mind tasks than the group with loss of all three genes. These results may reflect the influence of the GTF2I gene family on social cognition in Williams syndrome.

Lexical Relations in Spanish-Speaking Older Adults.

This study analyzed the types of lexical relations produced by Spanish-speaking older adults with typical aging. A total of 120 older adults completed a word association norms task with 117 stimulus words, which allowed us to explore differences in associations by sex, age, and years of education. We employed two classifications to code the lexical relations: a traditional classification (paradigmatic versus syntagmatic) and a second classification categorizing responses into 17 types of associations (e.g., categorial versus non-categorial). Our results show that participants have a preference for paradigmatic responses (e.g., dog-animal), as well as associations with thematic-contextual co-occurrence plus semantic relations (e.g., cradle-baby). These findings suggest that older adults tend to establish lexical relations based on a combined link, one that is semantic and contextual.

Atypical shape bias and categorization in autism: Evidence from children and computational simulations.

The shape bias, a preference for mapping new word labels onto the shape rather than the color or texture of referents, has been postulated as a word-learning mechanism. Previous research has shown deficits in the shape bias in children with autism even though they acquire sizeable lexicons. While previous explanations have suggested the atypical use of color for label extension in individuals with autism, we hypothesize an atypical mapping of novel labels to novel objects, regardless of the physical properties of the objects. In Experiment 1, we demonstrate this phenomenon in some individuals with autism, but the novelty of objects only partially explains their lack of shape bias. In a second experiment, we present a computational model that provides a developmental account of the shape bias in typically developing children and in those with autism. This model is based on theories of neurological dysfunctions in autism, and it integrates theoretical and empirical findings in the literature of categorization, word learning, and the shape bias. The model replicates the pattern of results of our first experiment and shows how individuals with autism are more likely to categorize experimental objects together on the basis of their novelty. It also provides insights into possible mechanisms by which children with autism learn new words, and why their word referents may be idiosyncratic. Our model highlights a developmental approach to autism that emphasizes deficient representations of categories underlying an impaired shape bias.

Verb-mediated anticipatory eye movements in people with Down syndrome.

BACKGROUND: Children and adults with neurotypical development employ linguistic information to predict and anticipate information. Individuals with Down syndrome (DS) have weaknesses in language production and the domain of grammar but relative strengths in language comprehension and the domain of semantics. What is not clear is the extent to which they can use linguistic information, as it unfolds in real time, to anticipate upcoming information correctly. AIMS: To investigate whether children and young people with DS employ verb information to predict and anticipate upcoming linguistic information. METHODS & PROCEDURES: A preferential looking task was performed, using an eye-tracker, with children and teenagers with DS and a typically developing (TD) control group matched by sex and mental age (average = 5.48 years). In each of 10 trials, two images were presented, a target and a distractor, while participants heard a phrase that contained a semantically informative verb (e.g., 'eat') or an uninformative verb (e.g., 'see'). OUTCOMES & RESULTS: Both DS and TD control participants could anticipate the target upon hearing an informative verb, and prediction skills were positively correlated with mental age in those with DS. CONCLUSIONS & IMPLICATIONS: This work demonstrates for the first time that children and teenagers with DS can predict linguistic information based on semantic cues from verbs, and that sentence processing is driven by predictive relationships between verbs and arguments, as in children with typical development. Clinicians can take advantage of these prediction skills, using them in therapy to support weaker areas.

Development of bidirectional phono-semantic activation in toddlers.

A mediated priming effect refers to the activation of a target via a mediator previously activated by a prime. This effect has been found at 24 months of age for phono-semantic links: a prime ( cup) activates a target ( dog) via a mediator ( cat), providing evidence of activation in a forward direction (phonological to semantic). Interactive models, however, propose that activation propagates in both forward and backward directions between processing levels. This study investigated the development of bidirectional co-activation of phonological and semantic levels of processing in Spanish-speaking toddlers. In a primed preferential looking task, participants were exposed to an unlabelled prime image, followed by the presentation of two images, a target and a distractor. In Experiment 1, when images with a semantic-phonological relationship were presented, both 24- and 30-month-olds preferred to look at the named target with a relationship to the prime image ( dog- cat- cup). However, when an unrelated target image was named, 24-month-olds preferred to look at the target, but 30-month-olds did not. In Experiment 2, both 24- and 30-month-olds preferred to look at a target with a phono-semantic relationship to the prime ( cup- cat- dog) over an unrelated target. These results provide strong evidence of differences in the development of forward and backward interactions between semantic and phonological processing levels.

The Impact of Household Size on Lexical Typicality: An Early Link Between Language and Social Cognition?

To communicate successfully, speakers need to use words that are understood by their listeners; they thus need to understand that others have vocabularies different than their own. A key question is whether this social cognition skill is already present in infancy, and whether it can have an impact on early language production. Analysis of the vocabularies of 550 Mexican children revealed that, at 24 months of age, but not at 18 nor at 30 months of age, those who were raised in households with larger numbers of children had more stereotypical vocabularies than those with fewer children. This finding is discussed in light of the hypothesis that communicative pressure may shape early word production; it suggests that bidirectional effects between social cognition and language acquisition are present at 2 years of age.

Pupil response and attention skills in Down syndrome.

Down syndrome (DS) is characterized by attentional problems. Little is known about the neural correlates of attention problems in DS due to difficulties in evaluation. Pupil dilation, associated with an increase in cognitive load and locus coeruleus-noradrenaline system activity in humans, is a neurophysiological measurement that may help to characterize such problems. The aim of this research was to investigate the link between a phasic pupil dilation response and target detection in people with DS, as compared with a control group with typical development (TD) matched by mental age. Participants performed an "oddball" task by means of an eye-tracker and a series of neuropsychological tests. Although the DS and control group demonstrated similar attentional skills and behavioral performance, the participants with DS showed greater pupil dilation. This result suggests that people with DS expend extra cognitive effort to achieve performance similar to those with TD. This finding is discussed in light of the attentional process in DS and the reliability of pupil dilation measurement in the study of attention and other cognitive processes in DS.

Developmental changes in maternal education and minimal exposure effects on vocabulary in English- and Spanish-learning toddlers.

The current research follows up on two previous findings: that children with minimal dual-language exposure have smaller receptive vocabularies at 16months of age and that maternal education is a predictor of vocabulary when the dominant language is English but not when it is Spanish. The current study extends this research to 22-month-olds to assess the developmental effects of minimal exposure and maternal education on direct and parent-report measures of vocabulary size. The effects of minimal exposure on vocabulary size are no longer present at 22months of age, whereas maternal education effects remain but only for English speakers.