Infants imitate others' individual actions, but do they also replicate others' joint activities? To examine whether observing joint action influences infants' initiation of joint action, forty-eight 18-month-old infants observed object demonstrations by 2 models acting together (joint action), 2 models acting individually (individual action), or 1…

Infants can track small groups of solid objects, and infants can respond when these quantities change. But earlier work is equivocal about whether infants can track continuous substances, such as piles of sand. Experiment 1 ("N" = 88) used a habituation paradigm to show infants can register changes in the size of piles of sand that they…

Mechanisms were examined to clarify relations between maternal depressive symptoms, dysfunctional cognitions, and infant night waking among 45 infants (1-24 months) and their mothers. A mother-driven mediational model was tested in which maternal depressive symptoms and dysfunctional cognitions about infant sleep predicted infant night waking via…

This longitudinal investigation of 84 infants examined whether the effect of 12-month attachment on 18- and 24-month exploration and sociability with unfamiliar adults varied as a function of newborn irritability. As expected, results revealed an interaction between attachment (secure vs. insecure) and irritability (highly irritable vs. moderately…

Bruner's (1973) review of infant skill development is updated and extended by (a) placing it in the context of recent motor learning research; (b) discussing the concept of efference in its most recent conceptualization; and (c) explicating certain implicit themes relevant to a theory of infant motor intelligence. (ED)

Examined relationship between emotion regulation at ages 5, 10, and 18 months, and compliance at 30 months. Found that infants with low levels of regulatory behavior were more likely to be noncompliant as toddlers. High cardiac vagal tone was related to noncompliance to toy clean-up, whereas low cardiac vagal tone was related to noncompliance to…

Examined differences in acoustic characteristics of cries, both early and late, within a prolonged crying bout. Results indicated that late cries appeared to result from a smaller number of factors than did early cries. Results support notions that crying bouts settle into a regular cry with acoustic features matching a theoretical model of cry…

A model of infant social behavior is developed which incorporates attachment to the familiar and fear of strangers as well as detachment from the familiar and exploration of the stranger. (JMB)

Theories of imitation learning are examined regarding their account of how the infant acquires the ability to emit a response which resembles a response previously exhibited by another. The role of cognition in imitation learning theory is discussed. (BRT)

Reveals that different aspects of the environment differentially contributed to variability in communication performance of one-year-old infants. Findings support the environmental specificity hypothesis and underline the need to consider physical environmental parameters when investigating environmental influences. (Author/RH)

Infant temperamental difficulty was strongly related to mothers' level of postpartum depression, both directly and through the mediation of parenting self-efficacy. Social support appeared to function protectively against depression, primarily through self-efficacy. Practical and theoretical implications are discussed. (Author/RH)

Meta-analysis of the A-not-B error was conducted, using logistic regression, on studies conducted before September 1997. Results replicated earlier findings, with exception that the number of trials at the A location was a significant predictor, and the number of locations was a significant predictor of the proportion of infants who searched…

Explored the antecedents and consequences of attachment disorganization among 157 participants in a prospective longitudinal study from 24 months to 19 years. Found that infant history of attachment disorganization was correlated with consequent variables related to: mother-child relationship quality at 24 and 42 months; child behavior problems in…

Calls for a process-oriented approach to study of categorization in infancy. Maintains that further understanding of infant categorization and its changes with development requires a more direct assessment of infants' category formation. Argues that two research directions will enhance understanding of categorization: (1) contextual variations on…