Examined fetal heart rate and movement in 31 healthy fetuses from 20 weeks through birth and at age 6 months. Found that more active fetuses were more difficult, unpredictable, unadaptable, and active as infants that were less active fetuses, and that higher fetal heart rate was associated with lower emotional tone, activity level, and…

Longitudinal data indicated a significant relation between five-month vagal tone and negative reactivity elicited in the laboratory and maternal ratings of activity level and smiling behavior. Newborn vagal tone predicted maternal ratings of frustration and fear. Moderate stability was found for infant reactivity. (RH)

To test the inversion of intensity interpretation based on negative relations between newborn and pre-school intensity behaviors, 106 normal children were examined at the neonatal and pre-school periods. Interpretations of intensity behaviors at both periods and their longitudinal relations are discussed. (Author/SB)

Examined cardiac activity during the first 13 months of life. Indexes of cardiac activity changed in an orderly way with development. There were intercorrelations among the cardiac measures. Analyses indicated that measures of heart-rate variability were significantly higher in insecure children than in secure children. (BC)