Examines the motivational or affective message and impact of infants' cries on nonparents, primiparous parents, and multiparous parents. Cries were organized into three levels (difficult, average, easy) by temperament ratings and spectographic analysis. Physiological and self-report responses to audiotapes of infants' cries were obtained from 36…

The reactions of 38 infants to two social stimuli (talking and smiling) as well as a nonsocial stimulus (a rotating musical mobile) were observed longitudinally when the infants were 4-, 12- and 20-weeks-old. (CM)

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…

Cardiac and behavioral reactions to strangers were measured in 5-, and 9-month-olds. Results indicate that: (1) behavioral differences between 5- and 9-month-olds are reflected in heart rate differences, (2) there are differences in heart rate but not behaviors when mothers are absent, and (3) heart rate response is linked to affective expression.…

Two experiments, involving a total of 12 subjects, demonstrated the role of adults as releasers of infant vocal sounds, indicating that both rate and percent of bursts of vocal sounds are increased by adult stimulation. Both response-dependent and response-independent social stimulation were effective when infants could see the adult's eyes. (GO)

An infant control habituation-recovery procedure was used to study 3-month-old infants' discrimination of sad, happy, and surprise facial expressions. (Author/JMB)

This paper was presented by the senior author at the Merrill-Palmer Institute Conference on Research and Teaching of Infant Development, February 13-15, 1969. (MH)

Twenty-two infants (6.7 to 12.3 months old) were tested on a visual-cliff apparatus both crawling and in a walker. Results suggest a maturation-based explanation of cliff-avoidance in infants. (CM)

Four groups of infants, 4 1/2 to 5 1/2 months of age, were presented with repeated speech stimuli which were synthesized exemplars of the sound, "baba," natural exemplars of "baba" or "kaba," or novel syllables on each trial. (RH)

Evaluated psychological mechanisms underlying imitation of facial actions in 40 newborn infants. Results showed imitation of head movement and a tongue-protrusion gesture. Subjects imitated from memory after displays had stopped. (RJC)

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…