Getting beyond the "convenience sample" in research on early cognitive development

Greater attention to socioeconomic status in developmental research can improve the external validity, generalizability, and replicability of developmental science

Psychological researchers have been criticized for making broad presumptions about human behavior based on limited sampling. In part, presumptive generalizability is reflected in the limited representation of sociodemographic variation in research reports. In this analysis, we examine time-trends in reporting of a key sociodemographic construct relevant to many aspects of child development-socioeconomic status (SES)-across six mainstream developmental journals (Infancy, Child Development, Developmental Science, Developmental Psychology, Infant and Child Development, and Infant Behavior & Development) between 2016 and 2022. Findings point to limited reporting of SES across developmental journals and across time. Reporting rates varied significantly by region and by topic of development. In terms of specific indicators of SES, there was consistent use of income and caregiver education as SES indicators. The epistemic costs of the lack of integration of socio-economic factors in developmental research are addressed. Pathways to greater integration of SES are proposed. RESEARCH HIGHLIGHTS: We analyzed reporting and representation of socioeconomic status in published studies on early child development. A large proportion of published studies did not report any socio-economic information. Suggestions for greater attention to socioeconomic status are proposed.

In models we trust: preregistration, large samples, and replication may not suffice

Despite discussions about the replicability of findings in psychological research, two issues have been largely ignored: selection mechanisms and model assumptions. Both topics address the same fundamental question: Does the chosen statistical analysis tool adequately model the data generation process? In this article, we address both issues and show, in a first step, that in the face of selective samples and contrary to common practice, the validity of inferences, even when based on experimental designs, can be claimed without further justification and adaptation of standard methods only in very specific situations. We then broaden our perspective to discuss consequences of violated assumptions in linear models in the context of psychological research in general and in generalized linear mixed models as used in item response theory. These types of misspecification are oftentimes ignored in the psychological research literature. It is emphasized that the above problems cannot be overcome by strategies such as preregistration, large samples, replications, or a ban on testing null hypotheses. To avoid biased conclusions, we briefly discuss tools such as model diagnostics, statistical methods to compensate for selectivity and semi- or non-parametric estimation. At a more fundamental level, however, a twofold strategy seems indispensable: (1) iterative, cumulative theory development based on statistical methods with theoretically justified assumptions, and (2) empirical research on variables that affect (self-) selection into the observed part of the sample and the use of this information to compensate for selectivity.

Embracing neurodiversity in doll play: Investigating neural and language correlates of doll play in a neurodiverse sample

Doll play may provide opportunities for children to rehearse social interactions, even when playing alone. Previous research has found that the posterior superior temporal sulcus (pSTS) was more engaged when children played with dolls alone, compared to playing with tablet games alone. Children's use of internal state language (ISL) about others was also associated with pSTS activity. As differences in social cognition are frequently observed in autistic people, we were interested in the brain and language correlates of doll play in children with varying levels of autistic traits. We investigated children's (N = 57, mean age = 6.72, SD = 1.53) use of ISL and their pSTS brain activity using functional near-infrared spectroscopy (fNIRS) as they played with dolls and tablet games, both alone and with a social partner. We also investigated whether there were any effects of autistic traits using the parent-report Autism Spectrum Quotient-Children's Version (AQ-Child). We found that the left pSTS was engaged more as children played with dolls or a tablet with a partner, and when playing with dolls alone, compared to when playing with a tablet alone. Relations between language and neural correlates of social processing were distinct based on the degree of autistic traits. For children with fewer autistic traits, greater pSTS activity was associated with using ISL about others. For children with more autistic traits, greater pSTS activity was associated with experimenter talk during solo play. These divergent pathways highlight the importance of embracing neurodiversity in children's play patterns to best support their development through play.

Talk of the Town mobile app platform: New method for engaging family in STEM learning and research in homes and communities

Children do not just learn in the classroom. They engage in "informal learning" every day just by spending time with their family and peers. However, while researchers know this occurs, less is known about the science of this learning-how this learning works. This is so because investigators lack access to those moments of informal learning. In this mini-review we present a technical solution: a mobile-based research platform called "Talk of the Town" that will provide a window into children's informal learning. The tool will be open to all researchers and educators and is flexibly adaptable to these needs. It allows access to data that have never been studied before, providing a means for developing and testing vast educational interventions, and providing access to much more diverse samples than are typically studied in laboratories, homes, and science museums. The review details the promise and challenges associated with these new methods of data collection and family engagement in STEM learning sciences.

Numeracy skills in young children as predictors of mathematical competence

As mathematical competence is linked to educational success, professional achievement, and even a country's economic growth, researchers have been interested in early predictors for quite some time. Although there have been numerous studies on domain-specific numerical abilities predicting later mathematical competence in preschool children, research in toddlers is scarce, especially regarding additional influential aspects, such as domain-general cognitive abilities and the children's social background. Using a large-scale dataset, the present study examined predictive effects of numeracy skills in 17-month-olds for later mathematical achievement. We found small, positive effects, even when controlling for child-related variables (i.e., age and sex) and the children's social background (i.e., maternal education and household language). Additionally, we compared results with a domain-general categorization task and found no distinct effect on mathematical competence. The present results are discussed with regard to the specificities of the dataset, as well as implications for future studies on predictors of mathematical competence.

Language input to infants of different socioeconomic statuses: A quantitative meta-analysis

For the past 25 years, researchers have investigated language input to children from high- and low-socioeconomic status (SES) families. Hart and Risley first reported a "30 Million Word Gap" between high-SES and low-SES children. More recent studies have challenged the size or even existence of this gap. The present study is a quantitative meta-analysis on socioeconomic differences in language input to young children, which aims to systematically integrate decades of research on this topic. We analyzed 19 studies and found a significant effect of SES on language input quantity. However, this effect was moderated by the type of language included in language quantity measures: studies that include only child-directed speech in their language measures find a large SES difference, while studies that include all speech in a child's environment find no effect of SES. These results support recent work suggesting that methodological decisions can affect researchers' estimates of the "word gap." Overall, we find that young children from low-SES homes heard less child-directed speech than children from mid- to high-SES homes, though this difference was much smaller than Hart & Risley's "30 Million Word Gap." Finally, we underscore the need for more cross-cultural work on language development and the forces that may contribute to it, highlighting the opportunity for better integration of observational, experimental, and intervention-based approaches.

Research at a Distance: Replicating Semantic Differentiation Effects Using Remote Data Collection With Children Participants

Remote data collection procedures can strengthen developmental science by addressing current limitations to in-person data collection and helping recruit more diverse and larger samples of participants. Thus, remote data collection opens an opportunity for more equitable and more replicable developmental science. However, it remains an open question whether remote data collection procedures with children participants produce results comparable to those obtained using in-person data collection. This knowledge is critical to integrate results across studies using different data collection procedures. We developed novel web-based versions of two tasks that have been used in prior work with 4-6-year-old children and recruited children who were participating in a virtual enrichment program. We report the first successful remote replication of two key experimental effects that speak to the emergence of structured semantic representations (N = 52) and their role in inferential reasoning (N = 40). We discuss the implications of these findings for using remote data collection with children participants, for maintaining research collaborations with community settings, and for strengthening methodological practices in developmental science.

Infant Cognitive Development and Stimulating Parenting Practices in Rural China

This study examines the prevalence of cognitive delay among infants and toddlers in rural China and its relationship with one of the potential sources of the observed delay: low levels of stimulating parenting practices (SPPs). Data were compiled from five distinct studies, resulting in a pooled sample of 4436 caregivers of 6-29-month-old infants. The sampling sites span five provinces in rural China. According to the data, on average, rates of delay are high-51 percent. The low rates of SPPs among our sample demonstrate that this may be one source of the high prevalence of delays. The results of the multivariate regression analysis reveal that reading books and singing songs are each significantly associated with an increase in infant cognitive score by 1.62 points (p = 0.003) and 2.00 points (p < 0.001), respectively. Telling stories to infants, however, is not significantly associated with infant cognitive scores. Our findings indicate that caregivers with different characteristics engage in various levels of stimulating practices and have infants with different rates of delay. Specifically, infants of better-educated mothers who have greater household assets are in families in which the caregivers provide more SPPs and have infants who score higher on the study's cognitive abilities scales.

Roll Out the Red Carpet: The 3rd Annual Awards for the Most Valuable Contributions to Psychotherapy

Every spring, media coverage emphasizes the "award season", highlighting contributions made by musicians, actors, and professional athletes. Unfortunately, psychologists are not included in these gala celebrations. It seems appropriate to take time to praise the hard work and dedication that is required to publish in an academic journal. The present article summarizes the results from the 3rd annual psychotherapy award program designed to highlight the valuable contributions made in eleven different categories. A total of 81 academic journals were reviewed for their articles published during 2019, and 150 papers were found useful and relevant to the field of psychotherapy. The list was then shortened to 44 articles that were organized into eleven award categories, and the best paper in each category was selected by a panel from the journal's editorial board. The hope is that all psychotherapists will value the contributions being made in these articles.

Variation is the universal: making cultural evolution work in developmental psychology

Culture is a human universal, yet it is a source of variation in human psychology, behaviour and development. Developmental researchers are now expanding the geographical scope of research to include populations beyond relatively wealthy Western communities. However, culture and context still play a secondary role in the theoretical grounding of developmental psychology research, far too often. In this paper, we highlight four false assumptions that are common in psychology, and that detract from the quality of both standard and cross-cultural research in development. These assumptions are: (i) the universality assumption, that empirical uniformity is evidence for universality, while any variation is evidence for culturally derived variation; (ii) the Western centrality assumption, that Western populations represent a normal and/or healthy standard against which development in all societies can be compared; (iii) the deficit assumption, that population-level differences in developmental timing or outcomes are necessarily due to something lacking among non-Western populations; and (iv) the equivalency assumption, that using identical research methods will necessarily produce equivalent and externally valid data, across disparate cultural contexts. For each assumption, we draw on cultural evolutionary theory to critique and replace the assumption with a theoretically grounded approach to culture in development. We support these suggestions with positive examples drawn from research in development. Finally, we conclude with a call for researchers to take reasonable steps towards more fully incorporating culture and context into studies of development, by expanding their participant pools in strategic ways. This will lead to a more inclusive and therefore more accurate description of human development.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'.

The choice is yours: Infants' expectations about an agent's future behavior based on taking and receiving actions

Our social world is rich with information about other people's choices, which subsequently inform our inferences about their future behavior. For individuals socialized within the American cultural context, which places a high value on autonomy and independence, outcomes that are the result of an agent's own choices may hold more predictive value than similar outcomes that are the result of another person's choices. Across two experiments we test the ontogeny of this phenomenon; that is, whether infants are sensitive to the causal history associated with an agent's acquisition of an object. We demonstrate that on average, 12.5-month-old American infants view taking actions as a better indication of an agent's future behavior than are receiving actions. Furthermore, there were significant individual differences in the extent to which infants perceived object receipt to be indicative of future behavior. Specifically, the less autonomous infants were perceived to be (by their parents), socialized to be, and behaved, the more they viewed object receipt as indicative of future behavior. The results are discussed in terms of the role of individual and cultural experience in early understanding of intentional action. (PsycINFO Database Record

Vocabulary size and auditory word recognition in preschool children

Recognizing familiar words quickly and accurately facilitates learning new words, as well as other aspects of language acquisition. This study used the visual world paradigm with semantic and phonological competitors to study lexical processing efficiency in 2-5 year-old children. Experiment 1 found this paradigm was sensitive to vocabulary-size differences. Experiment 2 included a more diverse group of children who were tested in their native dialect (either African American English or Mainstream American English). No effect of stimulus dialect was observed,. Results showed that vocabulary size was a better predictor of eye gaze patterns than maternal education, but that maternal education level had a moderating effect; as maternal education level increased, vocabulary size was less predictive of lexical processing efficiency.

From big data to deep insight in developmental science

The use of the term 'big data' has grown substantially over the past several decades and is now widespread. In this review, I ask what makes data 'big' and what implications the size, density, or complexity of datasets have for the science of human development. A survey of existing datasets illustrates how existing large, complex, multilevel, and multimeasure data can reveal the complexities of developmental processes. At the same time, significant technical, policy, ethics, transparency, cultural, and conceptual issues associated with the use of big data must be addressed. Most big developmental science data are currently hard to find and cumbersome to access, the field lacks a culture of data sharing, and there is no consensus about who owns or should control research data. But, these barriers are dissolving. Developmental researchers are finding new ways to collect, manage, store, share, and enable others to reuse data. This promises a future in which big data can lead to deeper insights about some of the most profound questions in behavioral science.

Assessing cognitive improvement in people with Down syndrome: important considerations for drug-efficacy trials

Experimental research over just the past decade has raised the possibility that learning deficits connected to Down syndrome (DS) might be effectively managed by medication. In the current chapter, we touch on some of the work that paved the way for these advances and discuss the challenges associated with translating them. In particular, we highlight sources of phenotypic variability in the DS population that are likely to impact performance assessments. Throughout, suggestions are made on how to detect meaningful changes in cognitive-adaptive function in people with DS during drug treatment. The importance of within-subjects evaluation is emphasized.

Influence of implantation age on school-age language performance in pediatric cochlear implant users

OBJECTIVE

This study examined specific spoken language abilities of 160 children with severe-to-profound sensorineural hearing loss followed prospectively 4, 5, or 6 years after cochlear implantation.

STUDY SAMPLE

Ninety-eight children received implants before 2.5 years, and 62 children received implants between 2.5 and 5 years of age.

DESIGN

Language was assessed using four subtests of the Comprehensive Assessment of Spoken Language (CASL). Standard scores were evaluated by contrasting age of implantation and follow-up test time.

RESULTS

Children implanted under 2.5 years of age achieved higher standard scores than children with older ages of implantation for expressive vocabulary, expressive syntax, and pragmatic judgments. However, in both groups, some children performed more than two standard deviations below the standardization group mean, while some scored at or well above the mean.

CONCLUSIONS

Younger ages of implantation are associated with higher levels of performance, while later ages of implantation are associated with higher probabilities of continued language delays, particularly within subdomains of grammar and pragmatics. Longitudinal data from this cohort study demonstrate that after 6 years of implant experience, there is large variability in language outcomes associated with modifiers of rates of language learning that differ as children with implants age.

SES differences in language processing skill and vocabulary are evident at 18 months

This research revealed both similarities and striking differences in early language proficiency among infants from a broad range of advantaged and disadvantaged families. English-learning infants (n = 48) were followed longitudinally from 18 to 24 months, using real-time measures of spoken language processing. The first goal was to track developmental changes in processing efficiency in relation to vocabulary learning in this diverse sample. The second goal was to examine differences in these crucial aspects of early language development in relation to family socioeconomic status (SES). The most important findings were that significant disparities in vocabulary and language processing efficiency were already evident at 18 months between infants from higher- and lower-SES families, and by 24 months there was a 6-month gap between SES groups in processing skills critical to language development.