Results suggest that temporal summation of brief stimuli is deficient in neonates. When compared with adult data from an analogous study, results also suggest that the transient system is immature in infants and that this immaturity is expressed in different ways by startle amplitude, probability, and latency. (PCB)

Evaluated psychological mechanisms underlying imitation of facial actions in 40 newborn infants. Results showed imitation of head movement and a tongue-protrusion gesture. Subjects imitated from memory after displays had stopped. (RJC)

Investigated newborns' responses to decreased sound pressure level (SPL) by means of a localized head turning habituation procedure. Findings, which demonstrated recovery of neonatal head turning to decreased SPL, were inconsistent with the selective receptor adaptation model. (RH)

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)

Responsivity to graded tactile stimuli was examined in human newborns in successive epochs of active and quiet sleep. Heart rate and behavior were both used as response indices. (Author/SS)

Three experiments examined whether newborns are sensitive to an operant-conditioning task involving unprepared relation between a response and a stimuli. Found that newborns tested under the High-Amplitude Sucking procedure were involved in an operant-learning situation, in that an increase in sucking rates could be obtained after an auditory…

Studied individual differences in reactivity in 40 newborns. Measures of reactivity were related during the first two months of extrauterine life. (RJC)

The infants of the adolescent mothers were found to be significantly less capable of responding to social stimuli, to be less alert, and to be less able to control motor behavior and to perform integrated motor activities than were the infants of older mothers. Journal availability: J. B. Lippincott Co., E. Washington Sq., Philadelphia, PA 19105.…

Reports that, even though young infants can discriminate among different facial expressions, there are individual differences in infants' expressivity and ability to produce and discriminate facial expressions. (PCB)

In three experiments, it was demonstrated that human newborn heart rate level can be reliably modified through classical conditioning procedures. Findings support the idea that early learning may occur under a variety of conditions and different theories may account for the results. (Author/SB)

Investigates intersensory interaction between auditory and visual stimulation in newborn infants. Following auditory stimulation, newborns' visual preferences for light patches of different intensity were examined. Results indicate that newborns attend to quantitative variations in stimulation and that these variations reflect both the objective…

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)