Compared everyday infant experiences among central Africa's Aka hunter-gatherers and Ngandu farmers. Found that Aka were more likely to be held, fed, and asleep or drowsy. Ngandu were more likely to be alone and to fuss or cry, smile, vocalize, or play. Crying, soothing, feeding, and sleeping declined over time for both; distal social interaction…

Evaluated respiratory sinus arrhythmia (RSA) and heart period in 5-month-olds during interaction challenges. Found that during object-mediated challenge, RSA increases were uniquely related to positive engagement. During person-mediated challenge, subjects showed more complex integration of autonomic and behavioral responses such that only infants…

Two experiments examined development of the ordinality concept in infants. Found that 11-month-olds successfully discriminated, whereas 9-month-olds failed to discriminate sequences that descended in numerical value from sequences increasing in numerical value. Nine-month-olds could discriminate the ordinal direction of sequences that varied in…

Assessed development of infants' sensitivity to two nested amodal temporal relations in audible and visible events. Found that sensitivity to synchrony was present by 4 weeks, remaining stable across age. Sensitivity to composition emerged by 7 weeks, increasing dramatically with age. Noted pattern of increasing specificity in perception…

A longitudinal study examined memory span at 5, 7, and 12 months in full-term and low-birth-weight preterm infants. Findings were similar for both groups: longer spans were more difficult, especially at younger ages, memory capacity increased over first year of life, there was marked recency effect for spans of 3 and 4 at all ages, and modest…

From Aesop to Sun Tzu, the importance of working together has long been acknowledged. Yet as long as cooperation has existed, so have the difficulties associated with it. Pooling two fields might mean twice the power, but this union also brings twice the jargon, twice the competing theories, and twice the head butting. Nonetheless, in this…

Attachment theorists assume that maternal mental representations influence responsivity, which influences infant attachment security. However, primary studies do not support this mediation model. The authors tested mediation using 2 mother-infant samples and found no evidence of mediation. Therefore, the authors explored sensitivity as a…

This study was designed to provide a general picture of infant vocal-motor coordination and test predictions generated by Iverson and Thelen's (1999) model of the development of the gesture-speech system. Forty-seven 6- to 9-month-old infants were videotaped with a primary caregiver during rattle and toy play. Results indicated an age-related…

Investigated early development of temperament across three cultures: People's Republic of China (PRC), United States of America (US), and Spain, utilizing a longitudinal design (assessments at 3, 6, and 9 months of age). Selection of these countries presented an opportunity to conduct Eastern-Western/Individualistic-Collectivistic comparisons. The…

Reddy and Trevarthen explore what we can learn from emotionally engaging with babies. Theirs is a different approach from 20th-century psychology, in which doubt and detachment play a role in discerning other people's feelings and thoughts. Instead, the authors suggest that emotions are the key to psychological engagement. When interacting with an…

Three major components have been repeatedly implicated for the origin(s) of sudden infant death syndrome (SIDS): system, minor sickness and surroundings. All these factors also frame infant temperament, and therefore it seems logical to suppose that the babies who either succumb to or are at risk of SIDS may present with certain behavioral…

Links between neonatal biological rhythms and the emergence of interaction rhythms were examined in 3 groups (N=71): high-risk preterms (HR; birth weight less than 1,000 g), low-risk preterms (LR; birth weight=1,700-1,850 g), and full-term (FT) infants. Once a week for premature infants and on the 2nd day for FT infants, sleep-wake cyclicity was…

Preferential-looking studies suggest that by 2 months of age, infants may have knowledge about some object properties, such as solidity. Manual search studies of toddlers examining these same concepts, however, have failed to provide evidence for the same understanding. Investigators have recently attempted to reconcile this disparity but failed…

Twenty-five newborn infants were tested for auditory-oral matching behavior when presented with the consonant sound /m/ and the vowel sound /a/--a precursor behavior to vocal imitation. Auditory-oral matching behavior by the infant was operationally defined as showing the mouth movement appropriate for producing the model sound just heard (mouth…

In the studies presented here, infants' understanding of others' attention was assessed when gaze direction cues were not diagnostic. Fourteen-, 18- and 24-month-olds witnessed an adult look to the side of an object and express excitement. In 1 experimental condition this object was new for the adult because she was not present while the child and…