Using electrocardiogram data with 78 six-month-old infants, this study examined the presence or absence of brief orienting bradycardia during the onset of maternal arm-restraint and subsequent differences between infants on behavioral organization during restraint. Results showed that 45 of the infants exhibited brief episodes of bradycardia at…

Infants often protest the activities of their caregivers, and this particular social interaction may provide an important window on early communication and its development. This study used naturalistic methods to investigate the development of vocal protests. Fifteen mother-infant dyads at each of 5 ages, from 3 to 18 months, were observed at…

Acoustic properties of the cries of 14 infants were evaluated at both 2 and 4 weeks of age when the infants were lying in a supine position and when they were sitting upright in a car seat. In the upright position, infants' breathing was more rapid and showed less individual variability. The fundamental frequency of their cries increased in the…

This study investigates individual differences in the contribution of specific maternal regulatory behaviors to the mother-infant dyad's regulation of infant distress response. Additionally, we examined the stability of infants' stress responses and the stability of specific maternal soothing behaviors. The sample included 128 mother-infant dyads…