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)

Investigates psychophysiological reactions of 60 women to an infant's cry and to a control sound. The 30-second pain cry evoked greater cardiac and electrodermal activity than did the control stimulus, although selected groups varied in the nature and extent of their reactions. Both maternal state and experience with infants affected reactions.…

To determine whether heart rate increase can be attributed to increased sucking amplitude for sweeter fluids, sucking and heart rate of 20 full-term infants were studied. (MP)

Twice during the neonatal period, the behavioral organization of 42 newborns was assessed by the Neonatal Behavioral Assessment Scale (NBAS), and the newborns' cortisol response to the NBAS procedure was determined. Newborns with low orientation showed a higher increase in cortisol during the NABS than newborns with high orientation. (MDM)

Examined behavioral/physiological responses of 2-month-olds during physical examinations. Found that colic infants cried twice as much, cried more intensely, and were more inconsolable than control infants. Heart rate, vagal tone, and cortisol measures showed no appreciable difference. At home, colic infants displayed a blunted rhythm in cortisol…

Examined visual fixation in 3- to 6-month olds for fit to attentional inertia theory. Found that look duration toward extended audiovisual stimuli had a lognormal distribution. The conditional probability of looking away decreased when look duration increased. Heart rate deceleration accompanied look onset and stimulus changes occurring within…

Classified fetuses as accelerators or decelerators based on intrapartum fetal heart rate (FHR). Explored the relationship of the classification with gestational age and neonatal behavior in clinically healthy neonates to provide an empirical basis for using FHR in the study of infant behavior. Subjects were 48 "healthy term" or…

Examined the sex differences in physiological and behavioral stress reactivity among 36 healthy, full-term neonates after a mildly stressful behavioral assessment procedure. Salivary cortisol, heart rate change, Neonatal Behavior Assessment Scale (NBAS) cluster scores, and behavioral states after the NBAS provided 100% discrimination between male…

Explored relation between temperament and cardiac vagal tone in 12-week olds. Found that infants with higher baseline vagal tone showed fewer negative behaviors in the laboratory and were less disrupted by experimental procedures than infants with lower baselines. Infants who decreased cardiac vagal tone during assessments were rated by mothers as…

Explores whether an empirical classification of healthy fetuses as fetal heart rate accelerators or decelerators would predict birth weight and neonatal behavior scored with the Brazelton Neonatal Behavior Assessment Scale. (Author/RH)

Investigates the relationship between cardiovascular reactions and five basic emotions, (interest, anger, fear, distress, and joy) exhibited by 40 9- and 12-month-old infants. (CM)

Assessed behavioral and physiological differences between 61 breast-fed and 39 bottle-fed neonates. Mean postpartum assessment occurred at 37 hours. Results suggest that breast-fed infants had significantly longer heart periods, elevated heart period variability, and higher vagal tone than bottle-fed infants. (Author/RWB)

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…

Investigated infants' reactions to the face-to-face/still-face paradigm. Infants reacted to the still-face with negative affect, a drop in vagal tone, and an increase in heart rate. By contrast, they reacted to the reunion episode with a mixed pattern of positive and negative affect. (HTH)