Psychological scientists have become increasingly concerned with issues related to methodology and replicability, and infancy researchers in particular face specific challenges related to replicability: For example, high-powered studies are difficult to conduct, testing conditions vary across labs, and different labs have access to different infant populations. Addressing these concerns, we report on a large-scale, multisite study aimed at (a) assessing the overall replicability of a single theoretically important phenomenon and (b) examining methodological, cultural, and developmental moderators. We focus on infants’ preference for infant-directed speech (IDS) over adult-directed speech (ADS). Stimuli of mothers speaking to their infants and to an adult in North American English were created using seminaturalistic laboratory-based audio recordings. Infants’ relative preference for IDS and ADS was assessed across 67 laboratories in North America, Europe, Australia, and Asia using the three common methods for measuring infants’ discrimination (head-turn preference, central fixation, and eye tracking). The overall meta-analytic effect size (Cohen’s d) was 0.35, 95% confidence interval = [0.29, 0.42], which was reliably above zero but smaller than the meta-analytic mean computed from previous literature (0.67). The IDS preference was significantly stronger in older children, in those children for whom the stimuli matched their native language and dialect, and in data from labs using the head-turn preference procedure. Together, these findings replicate the IDS preference but suggest that its magnitude is modulated by development, native-language experience, and testing procedure.
|Number of pages||29|
|Journal||Advances in Methods and Practices in Psychological Science|
|State||Published - 1 Mar 2020|
Bibliographical noteFunding Information:
Funding Data collection was supported by a grant from the Laura and John Arnold Foundation through the Association for Psychological Science. Individual participating labs further acknowledge funding support from the Natural Sciences and Engineering Research Council of Canada (Grants 12R81103, 2018-05823, and 402470-2011); the Social Sci-ences and Humanities Research Council of Canada (Insight Grant 12R20580); the United Kingdom’s Economic and Social Research Council (Grants ES/L008955/1 and ES/ N005635/1); the Agence Nationale de la Recherche (Grant ANR-17-EURE-0017); a European Research Council Synergy Grant (SOMICS, Grant 609819); the Alvin V., Jr. and Nancy C. Baird Professorship; the Korean National Research Fund (Grant NRF-2016S1A2A2912606); the U.S. National Insti-tutes of Health (Grants R03 HD079779 and R37 HD037466); Leibniz ScienceCampus Primate Cognition seed funds; The Science Academy, Turkey, Young Scientist Award Program (BAGEP); Research Manitoba, University of Manitoba; and Children’s Hospital Research Institute of Manitoba.
© The Author(s) 2020.