Young children's (n = 108) and adults' (n = 40) ability to compute ad-hoc quantity conversational implicatures was assessed using a new implicit task that relied on eye-tracking. The children were 2 and 5 years old. Looking times reveal that all participants interpreted simple references by relying on implicatures. However, 2-year-olds failed to…

A range of demographic variables influences how much speech young children hear. However, because studies have used vastly different sampling methods, quantitative comparison of interlocking demographic effects has been nearly impossible, across or within studies. We harnessed a unique collection of existing naturalistic, day-long recordings from…

For research on emotional development, defining emotions as psychological systems of appraisals, expressions, body reactions, and subjective feelings in all phases of ontogenesis raises tricky methodological issues. How can we measure single emotions when appraisals and feelings cannot be assessed from outside, when expressions do not seem to be…

This study compared the temporal measurements of stop consonants in 29 three- to six-year-old Mandarin-speaking children and 12 Mandarin-speaking adults. Each participant produced 18 Mandarin disyllabic words which contained six stop consonants /p, p?, t, t?, k, k?/ each followed by three vowels /a, i, u/ at the word-initial position in the first…

A talking face provides redundant cues on the mouth that might support language learning and highly salient social cues in the eyes. What drives children's looking toward the mouth versus eyes of a talking face? This study reports data from 292 children who viewed faces speaking English, French, and Russian. We investigated the impact of…

Word learning depends critically on the use of linguistic context to constrain the likely meanings of words. However, the mechanisms by which children infer word meaning from linguistic context are still poorly understood. In this study, we asked whether adults (n = 58) and 2- to 6-year-old children (n = 180) use discourse coherence relations…

Background: Although plausible links between language development and personality have been suggested, longitudinal studies of these associations into adulthood have not been conducted. Aim: To investigate whether children's age at attaining language milestones is associated with later adult personality. Methods: Mothers' of 8,400 children from…

Toddlers with an older sibling with autism spectrum disorder (ASD) and low risk (LR) toddlers were observed at 22, 28, and 34 months during two empathy probes: a crying baby and an adult who pretended to hurt her finger. Toddlers with a later ASD diagnosis showed less empathic concern and self-distress at each age on both empathy probes than LR…

Spontaneous verbal repetition is part of early adult-child conversational interchanges. However, most of the studies devoted to verbal repetition analyse child-produced and adult-produced repetition independently. The aim of this study is to analyse verbal repetition sequences that are extended by children and adults participating in turns. We…

Younger brains are noisier information processing systems; this means that information for younger individuals has to allow clearer differentiation between those aspects that are required for the processing task in hand (the "signal") and those that are not (the "noise"). We compared toddler-directed and adult-directed TV…

Joint attention has been suggested to contribute to children's development of cooperation; however, few empirical studies have directly tested this hypothesis. Children aged 1 and 2 years participated in two joint action activities to assess their cooperation with an adult partner, who stopped participating at a specific moment during the tasks.…

The study investigated the influence of universal and language-specific morpho-syntactic properties (i.e., flexible word order, case) on the acquisition of verb argument structures in German compared with English. To this end, 65 three- to nine-year-old German learning children and adults were asked to act out grammatical ("The sheep…

Although much research has examined the development of orienting to social directional cues (e.g., eye gaze), little is known about the development of orienting to nonsocial directional cues, such as arrows. Arrow cues have been used in numerous studies as a means to study attentional orienting, but the development of children's understanding of…

Recent studies indicate the need to investigate the sources of toddlers' understanding of another person's pretense. The present study is a cultural and longitudinal extension of the work of Lillard and Witherington (2004), who claimed that mothers modify their behaviors during pretense and that the some of these behavior modifications help their…

When face processing studies find sex differences, male infants appear better at face recognition than female infants, whereas female adults appear better at face recognition than male adults. Both female infants and adults, however, discriminate emotional expressions better than males. To investigate if sex and age differences in facial scanning…