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…

Prenatal and neonatal events were reported by parents of 13,690 eighteen-month-old twins enrolled in the Twins Early Development Study, a representative community sample born in England and Wales. At ages 7-8, parents and teachers completed questionnaires on social and nonsocial autistic-like features and parents completed the Childhood Asperger…

Examines the relation between aspects of the fundamental frequency (basic pitch) of 16 infant newborn cries and 28 multiparous mothers' perceptions of those cries. Results support the hypothesis that increases in fundamental frequency are related to increases in maternal perceptions of the intensity of the infant's cry. (Author/RWB)