Depression in mothers is consistently associated with reduced caregiving sensitivity and greater infant negative affect expression. The current article examined the real-time behavioral mechanisms underlying these associations using Granger causality time series analyses in a sample of mothers (N = 194; 86.60% White) at elevated risk for…

Independent locomotion is associated with a range of positive developmental outcomes, but unlike cognitive, linguistic, and social skills, acquiring motor skills requires infants to generate their own input for learning. We tested factors that shape infants' spontaneous locomotion by observing forty 12- to 22-month-olds (19 girls, 21 boys) during…

Infant motor development is affected by the sociocultural context in which it takes place. Because societal and cultural practices are dynamic, this exploratory study examined whether the ages at which infants typically learned to crawl, cruise, and walk changed over the past 3 decades. We compiled archival data from 1,306 infants born between…

How do age and the acquisition of independent walking relate to changes in infants' everyday experiences? We used a novel ecological momentary assessment (EMA) method to gather caregiver reports of infants' restraint, body position, and object holding via text messages sparsely sampled across multiple days of home life at 10, 11, 12, and 13 months…

Infants' sensitivity to transitional probabilities (TPs) supports language development by facilitating mapping high-TP (HTP) words to meaning, at least up to 18 months of age. Here we tested whether this HTP advantage holds as lexical development progresses, and infants become better at forming word--referent mappings. Two groups of 24-month-olds…

Infants' preference for vowelharmony (VH, a phonotactic constraint that requires vowels in a word to be featurally similar) is thought to be language-specific: Monolingual infants learning VH languages show a listening preference for VH patterns by 6 months of age, while those learning non-VH languages do not (Gonzalez-Gomez et al., 2019; Van…

While negative associations between behavioral inhibition/shyness and social competence are well established for children from Western cultures, the directions of these associations have been inconsistent for Chinese children, partly due to the ongoing social-cultural changes in China. Drawing from three samples of young Chinese children (born…

The study of infant gaze has long been a key tool for understanding the developing mind. However, labor-intensive data collection and processing limit the speed at which this understanding can be advanced. Here, we demonstrate an asynchronous workflow for conducting violation-of-expectation (VoE) experiments, which is fully "hands-off"…

Sometime before their second birthday, many children have a period of rapid expressive vocabulary growth called the vocabulary spurt. Theories of the underlying mechanisms differ: Accumulator models emphasize the accumulation of experience with words over time to yield a spurtlike pattern, while cognitive models attribute the spurt to cognitive…

Data from 83,423 parent reports of temperament (surgency, negative affectivity, and regulatory capacity) in infants, toddlers, and children from 341 samples gathered in 59 countries were used to investigate the relations among culture, gender, and temperament. Between-nation differences in temperament were larger than those obtained in similar…

The present study examined genetic, prenatal, and postnatal environmental pathways in the intergenerational transmission of anxiety and depressive symptoms from parents to early adolescents (when these symptoms start to increase), while considering timing effects of exposure to parent anxiety and depressive symptoms postnatally. The sample was…

Presenting pictures of faces side by side is a common paradigm to assess infants' attentional biases according to social categories, such as gender, race, and language. However, seeing static faces does not represent infants' typical experience of the social world, which involves people in motion and performing actions. Here, we assessed infants'…

A growing body of literature shows that adherence to some aspects of Western masculinity norms, including the suppression of emotional vulnerability, avoidance of seeking support from others, and exaggerated physical toughness, is associated with poorer psychological and social outcomes. While existing research suggests that parental gender…