Newborns discriminate schematic faces from scrambled faces.

Newborn attention to, and discrimination of, facelike patterns was examined in three experiments employing 35 one- to three-day-old infants. Differential eye tracking and head turning to three moving stimuli (a schematic face, a scrambled face, and a luminance-matched blank) were measured in two of the three experiments. The newborns turned their eyes and heads farther to follow patterned stimuli, containing facelike features, than to a luminance-matched blank, but they did not turn farther to a stimulus with the features arranged in a facelike manner compared to features scrambled. A third experiment tested newborns' ability to discriminate between the facelike and scrambled face patterns. Using an infant-controlled procedure, infants showed similar initial fixation times and similar numbers of trials to reach a 60% response decrement criterion to both patterned stimuli. Following habituation, novelty responding indicated that infants discriminated between the schematic face and the scrambled face patterns. Although infants did not show a preference for a facelike stimulus compared to a features-scrambled pattern in the present experiments, they could discriminate the two patterns based on the internal arrangement of the facial features.

The still-face effect in Chinese and Canadian 3- to 6-month-old infants.

Studies conducted in China examining cross-cultural differences in 3- to 6-month-olds used the still-face paradigm. In each study, 20 infants were in the experimental group (normal, still-face, normal interactions) and 20 in the control (3 normal periods). In Study 1, infants interacted with either their mother or their father; they looked and smiled less to the still-face of both parents. In Study 2, infants interacted with both their mother and a stranger, with order counterbalanced. Experimental groups showed similar still-face effects to both adults. The control group responded similarly to the stranger in both orders but responded less to their mother when she interacted 2nd. The data were compared with archival data from Canadian infants. Although Chinese infants took longer to begin smiling, responding was similar in both cultures, despite differences in mothers' behavior: Chinese mothers played with the infants' arms; Canadian mothers played with the legs.

Swaddling after heel lance: age-specific effects on behavioral recovery in preterm infants.

We examined responses of preterm infants to swaddling after a heel lance. Fifteen preterm infants from two postconceptional age (PCA) groups (Group 1: n = 7, PCA < 31 wk; Group 2: n = 8, PCA > or = 31 wk) were observed for 30 minutes during blood sampling followed by routine care; blood sampling followed by swaddling; and no blood sampling and routine care. In both groups, blood sampling resulted in concurrent increases in heart rate and state of arousal, in negative facial displays, and in reductions in blood oxygensaturation. After the blood was drawn, infants less than 31 weeks PCA exhibited an immediate and spontaneous return to behavioral patterns similar to those observed during the no-blood-sample condition, regardless of treatment condition. Infants 31 weeks PCA or older exhibited protracted behavioral disturbance that was significantly reduced by the use of swaddling. We discuss the significance of these findings.

Infant sensitivity to adult eye direction.

Adult eye direction was manipulated while adults interacted with 3-6 month-olds over closed-circuit television (Experiment 1) or in person (Experiment 2). Infants received 4 1-min interaction periods. For experimental groups, adult eye contact was maintained during Periods 1 and 3, and averted during Periods 2 and 4 (by viewing infants on a television monitor to maintain contingency). Control infants received eye contact during all periods. Experimental infants' smiling declined whenever adults looked away; their visual attention simply decreased across periods. Control infants showed little change in gaze or smiling across periods. The implications of these results for Baron-Cohen's model of infant theory of mind and Morton and Johnson's 2-process theory of infant face perception are discussed.

A nursing research utilization strategy for staff nurses in the acute care setting.

The importance of research-based nursing practice is well recognized. However, typically, strategies to incorporate research findings into nursing practice have not been evaluated in terms of staff nurse outcomes. Thus, the purpose of this project was to evaluate the effectiveness of a research utilization strategy for staff nurses in the neonatal intensive care unit of a community teaching hospital. This project was intended to serve as a model for the incorporation of research findings into nursing practice on other nursing units in the acute care setting.

Pattern and space perception in young infants.

Research is reviewed which reveals the surprisingly advanced perceptual skills of very young infants and some changes in these capacities which occur early in life; possible mechanisms which may underlie these changes are discussed. Newborns readily turn toward visual, auditory, and tactual stimulation, indicating that primitive localization systems operate at birth. However, their pattern perception appears to be more limited, with the notable exception of certain facial configurations which may have a privileged status. During the period from 1 to 3 months of life, auditory localization responses decrease substantially from neonatal levels while interest in visual patterns increases; indeed, during this period infants seem to become 'captured' by visual stimuli. By 4 months of age, infants turn rapidly and accurately towards off-centered sounds again, as they begin to reach for visible and invisible sounding objects. Between 3 and 4 months of age, they become sensitive to various types of static pattern regularities such as symmetry and other global configurational properties, and to dynamic aspects of faces (e.g. changes in facial expressions). Major structural maturation of the visual cortex at this age may underlie these new levels of auditory-visual spatial integration and pattern analysis abilities.

Neonatal movement response decrement and recovery to sounds as a function of stimulus intensity.

Response decrement, novelty response, and dishabituation of body movements to repeated presentations of a white noise stimulus of 66, 76, and 86 dB were studied in 89, 2-3-day-olds in the first epoch of active-quiet sleep following a feeding. Newborns receiving the 86 dB repeating stimulus had greater movement scores compared to those receiving the 76 dB intensity who, in turn, had greater movement scores than those receiving the 66 dB intensity. All groups demonstrated movement response decline following repeated stimulation and a novelty response was observed when either a 66 or 76 dB repeating stimulus was increased to 86 dB. A novelty response was not observed when intensity was decreased and dishabituation was not observed following a novelty response. For a white noise stimulus, these findings are more consistent with the selective adaptation than the habituation explanation of neonatal response decrement to repeated auditory stimulation.

Is visually guided reaching in early infancy a myth?

The issue examined was whether infants require sight of their hand when first beginning to reach for, contact, and grasp objects. 7 infants were repeatedly tested between 6 and 25 weeks of age. Each session consisted of 8 trials of objects presented in the light and 8 trials of glowing or sounding objects in complete darkness. Infants first contacted the object in both conditions at comparable ages (mean age for light, 12.3 weeks, and for dark, 11.9 weeks). Infants first grasped the object in the light at 16.0 weeks and in the dark at 14.7 weeks, a nonsignificant difference. Once contact was observed, infants continued to touch and grasp the objects in both light and dark throughout all sessions. Because infants could not see their hand or arm in the dark, their early success in contacting the glowing and sounding objects indicates that proprioceptive cues, not sight of the limb, guided their early reaching. Reaching in the light developed in parallel with reaching in the dark, suggesting that visual guidance of the hand is not necessary to achieve object contact either at the onset of successful reaching or in the succeeding weeks.

Adult tactile stimulation during face-to-face interactions modulates five-month-olds' affect and attention.

3 studies were designed to investigate infant responses to tactile stimulation during brief adult-infant interaction using a modified still-face (SF) procedure. When adults pose a neutral SF expression, infants decrease gazing and smiling at the adults, and some increase grimacing, relative to normal interaction periods. This SF effect was substantially reduced in Study 1 when mothers or strangers continued to touch infants during the SF period. In Studies 2 and 3, tactile versus visual and active versus passive aspects of adult touch were isolated during different SF periods. Visible, active adult hands unaccompanied by touch elicited infant attention, but not smiling, during the SF period. By contrast, active, not passive, adult touch substantially reduced the SF effect, even when the adult's hands were invisible. In the latter condition, infants continued to gaze and smile at the adult's SF. Thus, adult facial expressions are not the only modulator of infant affect and attention during social exchanges; adult touch appears to play an active role.

Maturation of human fetal responses to vibroacoustic stimulation.

Maturation of human fetal response to vibroacoustic stimulation was examined in 60 fetuses from 23 to 36 weeks gestational age. Subjects received vibroacoustic or no-stimulus control trials (randomly assigned) while fetal heart rate (FHR) was recorded and movement was observed on real-time ultrasound scan. Initially, at 26-28 weeks, a small FHR deceleration response occurred; subsequently, FHR acceleration responses occurred. From 29 weeks, 83%-100% of subjects responded with an FHR acceleration > or = 10 BPM on the first vibrator trial and accelerations were observed on 83%-92% of all vibrator trials. From 26 to 36 weeks the percentage of fetuses responding with movement on the first vibrator trial increased from 58% to 100%; on all vibrator trials responses increased from 53% to 94%. It was concluded that maturation of human fetal response to vibroacoustic stimulation begins at about 26 weeks gestation, increases steadily over a 6-week period, and reaches maturity at about 32 weeks.

Mortality and morbidity after intrapartum asphyxia in the preterm fetus.

This matched cohort study examined the significance of intrapartum fetal asphyxia determined biochemically in the preterm newborn in regard to outcome during the first year. Thirty preterm newborns with metabolic acidosis at delivery were compared with 60 preterm newborns, matched for birth weight, with normal blood gas measures. Deaths during the first year were reviewed. Assessment of the surviving children at 1 year corrected age included neurologic examination, Bayley scales, and Uzgiris and Hunt scale to define motor and cognitive development. Seven asphyxiated infants (23%) died during the first year compared with two nonasphyxiated infants (3%), a statistically significant difference (P less than .006). Among the surviving children, the incidence of minor motor and/or cognitive deficits was the same in the two groups. The incidence of major motor and/or cognitive deficits in the group with asphyxia (eight of 30) was significantly greater than in the control group (eight of 60) (P less than .03). These results indicate that intrapartum fetal asphyxia in the preterm newborn is a contributing factor to the mortality and morbidity observed in these children.

Maternal and ultrasound measurements of elicited fetal movements: a methodologic consideration.

Two methods of evaluating fetal movement responses elicited by vibroacoustic stimulation--maternal perceptions and ultrasound scan observations--were compared in 58 low-risk and 35 high-risk pregnancies from 23-36 weeks' gestation. Maternal perception of vibrator-elicited fetal movement was poor compared with ultrasound scan observation. Regardless of gestational age or risk status, the mothers perceived 27-75% fewer movements than observed with ultrasound scan. In addition, maternal movement perceptions on vibrator versus no-stimulus control trials were not reliable until 29-32 weeks' gestation, with the percentage of movement responses increasing across gestation from 11 to 48%. In contrast, ultrasound scan observations of movement were reliable on vibrator compared with no-stimulus control trials from 26 weeks, with the percentage of movement responses increasing from 22% at 23-25 weeks to 94% at 35-36 weeks. We conclude that maternal perceptions of fetal movements cannot be substituted for ultrasound scan observations for accurate assessment of fetal movements during vibroacoustic stimulation testing.

The association of intrapartum asphyxia in the mature fetus with newborn behavior.

A matched cohort study of mature newborns with biochemically determined intrapartum fetal asphyxia and mature newborns with normal blood gas and acid-base assessments at delivery were studied to demonstrate the effect of fetal asphyxia on newborn behavior as expressed by the Brazelton newborn behavioral assessment scale. The newborn behavioral assessment scale was administered 3 days after delivery and again 2 weeks after delivery. The Lester newborn behavioral assessment scale summary scores for the group with asphyxia were of the same order as those in the control group. This was also true of the group of newborns with asphyxia with the more severe metabolic acidosis and those with low Apgar scores. These findings support the contention that many newborns who have undergone an intrapartum asphyxial insult will not have evidence of central nervous system injury and that the threshold of central nervous system injury is at the severe end of the spectrum of asphyxia as expressed by a metabolic acidosis.

Maturation of responses elicited by a vibroacoustic stimulus in a group of high-risk fetuses.

The study was designed to characterize the changes in fetal heart rate (FHR) and movement responses in a group of high-risk fetuses to address the question of differential responding as a function of risk status. The study included 36 women admitted to hospital with threatened preterm labour (e.g., contractions, bleeding, premature rupture of membranes) with singleton pregnancies between 23 and 34:6 weeks gestational age. Each fetus received three vibration and three no-stimulus control trials, intermixed and randomly presented. Vibration trials consisted of a 2.5-second (s) application of the tip of a battery-powered, hand-held commercial vibrator to the maternal abdomen over the site of the fetal head while the FHR was recorded continuously and movements were scored from a cross section of the infant's abdomen viewed with a real-time ultrasound scanner. FHR within 20 s and movements within 5 s of trial onset were scored blind as to vibration or control trial. Repeated measures ANOVA demonstrated that fetuses responded to vibration with FHR accelerations from 29 weeks and movements from 26 weeks. Although movements increased with increasing gestational age, the mean peak FHR acceleration showed no significant increase from 29 to 32 weeks. From 29 weeks, the latency to response was 5 s and the peak of the acceleration occurred at about 10 to 12 s. At 26-28 weeks, a small but reliable cardiac deceleration occurred at about 5 s after stimulus onset. These preliminary findings suggest a maturation of fetal sensitivity to vibroacoustic stimulation which is similar for groups of low-risk and high-risk fetuses. However, the variability in outcome--from preterm newborn death to "healthy" term delivery--in the high-risk group suggests that the sample may be heterogeneous.

The development of a human auditory localization response: a U-shaped function.

Research during the past 10 years on the neonatal head-turn response to off-centred rattle sounds is reviewed, and various procedural and stimulus conditions that influence the probability of eliciting a correct response are identified. Also, the existence of a U-shaped developmental function is confirmed in a cross-sectional study of 104 infants between 3 days and 7 months of age. Neonates responded reliably, but slowly; the response decreased in frequency and magnitude between 1-3 months of age and increased again by 4-5 months of age. Speculation that this U-shaped function reflects a maturational shift in locus of control from subcortical to cortical structures was supported by the infants' responses to the presence effect (PE), which is thought to be cortically mediated. The PE was produced by playing the rattle sound through two loudspeakers with the output of one delayed by 5 ms, relative to the other; adults perceive only one sound at the leading loudspeaker. As predicted, neonates failed to respond to the PE, and the onset of correct PE responses corresponded closely to the upswing in the U-shaped function for SS responses. Other explanations for the temporary decline in orientation responses to sound are also discussed.

Human fetal responses to sound as a function of stimulus intensity.

The effect of stimulus intensity on fetal heart rate (FHR) acceleration and body movement responses was evaluated in term fetuses in a two-stage study. During the first stage (N = 30), a pink noise played at 110 or 105 dB elicited a greater mean peak FHR acceleration than when played at 100 dB. Movement scores indicated that the 110-dB noise elicited more movements than the 105-dB noise which, in turn, elicited more than the 100-dB noise. The FHR acceleration and movement responses elicited on 100-dB sound trials could not be differentiated from spontaneous activity on no-sound control trials. During the second stage (N = 93), the 110-dB pink noise elicited a mean peak FHR acceleration of 14 beats per minute on the first stimulus presentation, replicating the findings of the first stage. Furthermore, the percentage of 110-dB stimulus/control trials in which there was an FHR acceleration greater than ten beats per minute (stage 1: 57%/10%; stage 2: 58%/24%) and movement response (stage 1: 50%/7%; stage 2: 52%/7%) was virtually identical in the two stages. We conclude that fetal response varies as a function of stimulus intensity and that the threshold for response to an air-borne pink noise is between 100-105 dB. These findings have implications for stimulus selection and control procedures in acoustic stimulation testing.

Development of infant reaching in the dark to luminous objects and 'invisible sounds'.

Two studies were conducted to investigate the existence of an unusual U-shaped developmental function described by Wishart et al (1978) for human infants reaching towards invisible sounds. In study 1, 2-7 month olds were presented with four conditions: (i) an invisible auditory stimulus alone, (ii) a glowing visual stimulus alone, (iii) auditory and visual stimuli on the same side (ie combined), and (iv) auditory and visual stimuli on opposite sides (ie in conflict). Study 2 was designed to examine the effects of practice and possible associations made when using the 'combined conflict' paradigm. Infants of 5 and 7 months of age were given five trials with the auditory stimulus, with or without prior visual experience, and five trials with the visual stimulus, with the position of the stimulus varied on each trial. Stimuli were presented individually at the midline, and +/- 30 and +/- 60 degrees from the midline. In both studies testing was conducted in complete darkness. Results indicated that the auditory-alone condition was slower to elicit a reach from the infants, relative to the visual-alone one, and reaches were least frequent to the auditory target. No U-shaped function was obtained, and reaching for auditory targets occurred later in age than for visual targets, but even at 7 months of age did not occur as often and was achieved by fewer infants. In both studies the quality of the reach was significantly poorer to auditory than to visual targets, but there were some accurate reaches. This research adds to our understanding of the development of auditory-manual coordination in sighted infants and is relevant to theories of auditory localization, visually guided reaching, and programming for the blind.

Motor and cognitive deficits after intrapartum asphyxia in the mature fetus.

The incidence of major and minor motor and/or cognitive deficits at 1 year of age, in 37 mature children who had experienced an intrapartum fetal asphyxial insult, was compared with the incidence of deficits at 1 year in 76 children of the control group. The incidence of both major and minor deficits was significantly greater in the group with intrapartum fetal asphyxia in relation to the control group. These findings support the concept that, beyond a critical threshold of fetal asphyxia, a continuum of casualty in the surviving newborn infants exists.