Search

Young children acquire a wide range of linguistic and cognitive skills in the first three years of life. Decades of experimental work have established a solid empirical foundation for our understanding of cognitive development. But most experimental studies are limited in statistical power and focus on specific psychological constructs, thus making them unsuitable for describing developmental growth at scale. Here, we turned to meta-analyses of experimental research. We conducted a meta-meta-analysis to consolidate and integrate 23 meta-analyses compiled on MetaLab, a community-augmented meta-analysis platform. We found that most datasets can not meaningfully distinguish different functional forms for developmental change, but in those that could, there is great diversity in the best-fitting functional forms of the age model. We also evaluated the impact of a range of methodological factors. Overall, our work sheds light on the heterogeneous nature of developmental trajectories and the subtle interactions between research methods and experimental outcomes.

Does knowing certain words help children learn other words? We hypothesized that knowledge of more general (more superordinate) words at time1 would lead to faster vocabulary growth as measured through vocabulary checklists administered at later timepoints. We find that this is indeed the case. Children who have similar vocabularies at time1 , but differ in their productive knowledge of more general words such as “animal,” “picture,” and “get” go on to have different rates of word learning. Knowledge of more general words is associated with faster vocabulary growth, particularly of words semantically related to the superordinate terms they are reported to produce. This positive relationship between knowledge of more general words and word learning remains even when controlling for measures of verbal and nonverbal intelligence.

The study of mental representations of concepts has historically focused on the representations of the “average” person. Here, we shift away from this aggregate view and examine the principles of variability across people in conceptual representations. Using a database of millions of sketches by people worldwide, we ask what predicts whether people converge or diverge in their representations of a specific concept, and which kinds of concepts tend to be more or less variable. We find that larger and more dense populations tend to have less variable representations, and concepts high in valence and arousal tend to be less variable across people. Further, two countries tend to have people with more similar conceptual representations when they are linguistically, geographically, and culturally similar. Our work provides the first characterization of the principles of variability in shared meaning across a large, diverse sample of participants.

The ability to rapidly recognize words and link them to referents in context is central to children's early language development. This ability, often called word recognition in the developmental literature, is typically studied in the looking-while-listening paradigm, which measures infants' fixation on a target object (vs. a distractor) after hearing a target label. We present a large-scale, open database of infant and toddler eye-tracking data from looking-while-listening tasks. The goal of this effort is to address theoretical and methodological challenges in measuring vocabulary development. We present two analyses of the current database (N=1,320): (1) capturing age-related changes in infants' word recognition while generalizing across item-level variability and (2) assessing how a central methodological decision -- selecting the time window of analysis -- impacts the reliability of measurement. Future efforts will expand the scope of the current database to advance our understanding of participant-level and item-level variation in children's vocabulary development.

How do children infer the meaning of a novel verb? One prominent proposal is that children rely on syntactic information in the linguistic context, a phenomenon known as "syntactic bootstrapping". For example, given the sentence "The bunny is gorping the duck," a child could use knowledge of English syntactic roles to infer that "gorping" refers to an action where the bunny is acting in some way on a duck. Here, we examine the strength of the syntactic bootstrapping effect, its developmental trajectory and generalizability using meta-analytic methods. Across 60 experiments in the literature (N = 849 participants), we find a reliable syntactic bootstrapping effect (d = 0.24). Yet, despite its theoretical prominence, the syntactic bootstrapping effect is relatively small, comparable in size to cross-situational learning and sound symbolism, but smaller than mutual-exclusivity and gaze-following. Further, we find that the effect does not strengthen over development, and is present only for studies that use transitive sentences. An examination of a range of methodological factors suggests that the effect is not strongly influenced by methodological implementation. In the General Discussion, we consider implications of our findings for theories of verb learning and make recommendations for future research.

Cultural norms vary dramatically across social groups. Herewe use large scale data to examine the extent to which languageplays a role in shaping one such norm—the gender norm to as-sociate men with careers and women with family. We measurecross-cultural variability in this gender bias using previously-collected estimates from the Implicit Association Task (IAT; N= 663,709). We then try to predict bias variability by the waythat gender is encoded in language semantics and grammar.We quantify gender bias in semantics using word-embeddingmodels trained on different languages. Our data suggest thatthe linguistic encoding of gender predicts the degree of speak-ers’ gender bias in the IAT, pointing to a causal role for lan-guage in shaping gender norms.

Meta-analysis is a powerful yet underused tool in cognitive sci-ence. It allows researchers to leverage entire bodies of litera-ture to get a broad and quantitative overview of a particularphenomenon, thereby promoting theory development, and tomake more precise estimates of effect sizes, which enablesrobust planning of prospective studies (e.g. through power-analyses). In this tutorial, we will introduce meta-analysis as atool with which to inform everyday research, and provide par-ticipants with hands-on experience conducting their own meta-analysis. We will also present an online platform we have de-veloped for conducting meta-analyses in the field of languagedevelopment: MetaLab (http://metalab.stanford.edu).

What accounts for the vast diversity in the world’s languages?We explore one possibility: languages adapt to their linguis-tic environment (Linguistic Niche Hypothesis; Lupyan & Dale,2010). Recent studies have found support for this hypothesisthrough correlations between aspects of the environment andlinguistic structure. We synthesize this previous work and findthat languages spoken in cold, small regions tend to be morecomplex across a range of linguistic features. We also testa novel prediction of the Linguistic Niche Hypothesis by ex-amining the learnability of languages for first-language, childlearners.

The emergence of language around a child’s first birthday isone of the greatest transformations in human development.Does this transition require a fundamental shift in the child’sknowledge or beliefs, or could it instead be attributable to moregradual changes in processing abilities? We present a simplemodel of cognitive performance that supports the second con-clusion. The premise of this model is that any cognitive op-eration requires multiple steps, each of which require sometime to complete and have some probability of failure. Weuse meta-analysis to estimate these parameters for two com-ponents of simple ostensive word learning: social cue use andword recognition. When combined in our model, these esti-mates suggest that learning should be very difficult for chil-dren younger than around a year, especially with gaze alone.This model takes a first step towards quantifying performancelimitations for cognitive development and may be broadly ap-plicable to other developmental changes.

Although natural languages are generally arbitrary in theirmapping of forms to meanings, there are some detectable biasesin these mappings. For example, longer words tend torefer to meanings that are more conceptually complex (whatwe refer to as a complexity bias; Lewis, Sugarman, & Frank,2014). The origins of this bias remain an open question, however.One hypothesis is that this lexical regularity is the productof a complexity bias in individual speakers, and that itemerges in the lexicon over the course of language evolution.In the present work, we use an iterated learning paradigm to explorethis proposal. Speakers learned labels of varying lengthsfor objects of varying complexity, and then were asked to recallthe learned labels. We then presented the labels that participantsproduced to a new set of speakers, iterating this procedureacross generations. The results suggest the presence of acomplexity bias that guides language change but that interactswith pressures for simplicity

Previous work suggests that key factors for replicability, a necessary feature for theory building, include statistical power and appropriate research planning. These factors are examined by analyzing a collection of 12 standardized meta-analyses on language development between birth and 5 years. With a median effect size of Cohen's d = 0.45 and typical sample size of 18 participants, most research is underpowered (range = 6%-99%; median = 44%); and calculating power based on seminal publications is not a suitable strategy. Method choice can be improved, as shown in analyses on exclusion rates and effect size as a function of method. The article ends with a discussion on how to increase replicability in both language acquisition studies specifically and developmental research more generally.

Rumble Fish, based on the young adult novel published by S.E. Hinton in 1975 and made into a film by Francis Ford Coppola in 1983, is often overshadowed by Hinton's more popular 1967 novel and Coppola's more successful film, The Outsiders, from earlier in 1983, even though the later film, Rumble Fish, has been discussed by a few notable scholars of teen cinema. This article examines why Rumble Fish, which centers on a juvenile delinquent and his elusive brother, failed to attract an audience during the time of its release. A detailed comparison of the novel and the film as well as an analysis of Coppola's director's commentary reveals that Coppola's autobiographical touches resulted in a film that provokes a varied subjective and emotional response from its viewers. The film, like the novel, is constructed as a memory. Rumble Fish is best understood as a nostalgic exploration of Coppola's own feelings regarding his boyhood rather than as a universal coming-of-age tale. KEYWORDS art, coming-of-age, film, memory, teenagers, S.E. Hinton, In 1983, Francis Ford Coppola presented to the audience of the New York Film Festival a film that he intended to be 'an art film for teenagers' (Coppola 2005). Rumble [...]