Verbs may refer to the means (I bumped into the lamp) or outcome (I broke the lamp) of an action (cf. Rappaport Hovav & Levin, 2010; Talmy, 1985). Do young children expect language to encode this distinction? Children’s imitation patterns suggest that they analyze nonlinguistic events in these terms. When a head-touch is the simplest action available, toddlers include just the outcome, not the means, in their own imitation (Gergely, Bekkering, & Király, 2002). We ask whether syntax influences this inference. An experimenter with her hands occupied made a toy activate with a headtouch, using either Means-focused (I’m daxing to my toy) or Outcome-focused language (I’m daxing my toy). Toddlers then imitated the action. Means- but not Outcome-focus language encouraged children to include the distinctive headtouch, overriding the standard ‘rational imitation’ effect. This suggests that toddlers’ knowledge of argument structure includes an understanding of a means/outcome divide in verb meaning.

Causal relationships can generate many different kinds of correlations among variables. However, research on children’s causal reasoning has focused almost exclusively on just one kind of regularity: the temporal covariation between candidate causes and effects, and in particular, the covariation between interventions and outcomes. Here we show that young children recognize more abstract correlations – in the ways that object properties are distributed over sets, or change over time – and constrain their causal hypotheses accordingly. Specifically, we show that children (range: 48-84 months) distinguish candidate causes based on correlations in the distribution of discrete (set size, arity, and proportion) and continuous (mean and mode) properties of sets (Experiment 1), and also within monotonic, quadratic, and periodic functions (Experiment 2). Keywords: children; causal reasoning; abstract concepts; sets; functions

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.