To investigate possible influences on and consequences of mothers' speech, specific infant behaviors preceding and following four pragmatic categories of mothers' utterances--responsive utterances, supportive behavioral directives, intrusive behavioral directives, and intrusive attentional directives--were examined longitudinally during dyadic…

We examined two aspects of temperamental approach in early infancy, positive reactivity and anger, and their unique and combined influences on maternal reports of child surgency and attention focusing at 4 years of age. One hundred and fourteen infants were observed for their positive reactions to novel stimuli at 4 months, and their anger…

Behne, Carpenter, Call, and Tomasello (2005) showed that 9- to 18-month-olds, but not 6-month-olds, differentiated between people who were unwilling and unable to share toys. As the outcome of the two tasks is the same (i.e., the toy is not shared), the infants must respond to the different goals of the actor. However, visual habituation paradigms…

Although a large literature discusses infants' preference for infant-directed speech (IDS), few studies have examined how this preference might change over time or across listening situations. The work reported here compares infants' preference for IDS while listening in a quiet versus a noisy environment, and across 3 points in development: 4.5…

Infant cortisol and behavioral responses to receiving one versus two inoculations on one pediatric office visit were observed at two and six months of age. The findings indicate a developmental trend for a decline over age in adrenocortical reactivity to inoculation for infants showing a cortisol release following perturbation. Results were…

Assessed delayed-response performance in 120 infants 7, 9, and 11 months old. Correct response was identified as either retrieval of a hidden object or a gaze toward its location. Performance improved with age, was above chance for each age group in each condition, and was more often correct for gaze response, suggesting a significant effect of…

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…

The relationship between visual stimulus intensity and directional finger movements was examined in infants of two age groups (16 infants, 10 to 15 weeks old, and 8 infants, 20 to 25 weeks old). Two hypotheses derived from Schneirla's Approach-Withdrawal Theory were examined: (1) that responses of the younger, but not of the older infants, would…

A total of 80 infants, divided equally among 4 age groups, participated in a contingency learning task. Of these infants, 48 received an audiovisual stimulus contingent on arm movement, and 32 served as a yoked control group. Findings indicated that exposure to a period in which the infant's expectancy regarding contingent outcomes is violated…

This paper describes the initial organization of the infant's reaction to having his vision occluded by an opaque cloth; traces the development of this reaction over the first six months; and probes the role the occlusion of vision plays in provoking the reaction. Fifty videotaped sessions of infants during two conditions - eyes covered with an…

To document movement patterns and to examine developmental interrelationships, the ontogeny of rooting, lip, lateral tongue, mouth opening, biting, and Babkin reflexes and the development of emerging chewing behaviors were observed in two normal infants over a period from 1 week to 35 weeks of age. (Author/RH)

Development of object identity was studied within the framework of a hiding game that varied the objects themselves instead of their spatial positions. (Authors)

Four facial stimuli derived from the Bolton standards of craniofacial development representing a human male at 6 months, 3, 8, and 18 years of age were used in a test of Lorenz's concept of babyishness and of the discrepancy hypothesis. Subjects were 87 four-month-old infants. (Author/MP)