ABSTRACT
Temperament was assessed for newborn twins, using a comprehensive neonatal exam that focused on irritability, resistance to soothing, activity, and reinforcement value. Emotional activity appeared to be the core dimension stretching over ages, and it is discussed in relation to other formulations of infant temperament. The infant's behavior was rated from videotapes by trained observers to yield a composite measure of each infant's temperament profile. The newborn infants were recruited as part of an ongoing longitudinal study of twins. After the lab session was completed, the infant was undressed and measured for head circumference, weight, and recumbent length. Infants who were emotionally positive during the lab vignettes were also likely to be attentive, active, socially oriented to the staff, and not upset by the restraints of physical measurements. The infants who were more reinforcing as neonates were more positive and good-humored at 9 months.
