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Brush or delta brush is a well-known characteristic waveform in preterm electroencephalograms. However, the longitudinal trajectory of brushes and its association with neurodevelopment remain uncertain.We analyzed the longitudinal incidence of brushes in 36 extremely low birth weight infants without severe brain lesions and its association with neurodevelopment and white matter abnormality. Conventional eight-channel electroencephalograms were recorded at 30, 32, 36, and 40 postmenstrual weeks (PMW). Incidence of brushes was calculated as the sum of brushes from each channel separated by active sleep and quiet sleep. A developmental delay was defined as a developmental quotient of85 assessed at corrected age of 18 months. White matter abnormalities were evaluated with term-equivalent magnetic resonance imaging.The median incidence of brushes (per minute) in 36 infants at PMW 30, 32, 36, and 40 was 16.4, 20.4, 22.5, and 1.8 during active sleep and 7.5, 10.3, 11.5, and 1.7 during quiet sleep, respectively. Among the 36 infants, 14 infants were diagnosed with developmental delay. Longitudinal trajectories of the incidence of brushes were different between the normal and the delayed development groups. Brushes were observed most frequently at 36 PMW in the delayed development group. The incidence of brushes at 36 PMW was significantly correlated with the severity of white matter abnormalities and negatively correlated with the developmental quotient.The incidence of brushes at 36 PMW can be a unique predictor of early neurodevelopment in extremely low birth weight infants without severe brain lesions.

Highlights • Higher power of cortical bursts after postnatal day 3 predicted worse cognitive, language and motor outcomes. • Association between cortical bursts and outcome was independent of structural MRI findings. • EEG may provide additional information by indexing persistent active mechanisms that support recovery or exacerbate damage., Objective Early prediction of neurological deficits following neonatal hypoxic-ischemic encephalopathy (HIE) may help to target support. Neonatal animal models suggest that recovery following hypoxia-ischemia depends upon cortical bursting. To test whether this holds in human neonates, we correlated the magnitude of cortical bursting during recovery (≥postnatal day 3) with neurodevelopmental outcomes. Methods We identified 41 surviving infants who received therapeutic hypothermia for HIE (classification at hospital discharge: 19 mild, 18 moderate, 4 severe) and had 9-channel electroencephalography (EEG) recordings as part of their routine care. We correlated burst power with Bayley-III cognitive, motor and language scores at median 24 months. To examine whether EEG offered additional prognostic information, we controlled for structural MRI findings. Results Higher power of central and occipital cortical bursts predicted worse cognitive and language outcomes, and higher power of central cortical bursts predicted worse motor outcome, all independently of structural MRI findings. Conclusions Clinical EEG after postnatal day 3 may provide additional prognostic information by indexing persistent active mechanisms that either support recovery or exacerbate brain damage, especially in infants with less severe encephalopathy. Significance These findings could allow for the effect of clinical interventions in the neonatal period to be studied instantaneously in the future.

The aim was to examine the interrelationship between sleep quality of 1-month infants and mothers, mothers’ corresponding activities to infant’s night sleep, and mother’s mental health. A cross-sectional survey with self-reported questionnaire was conducted among 437 healthy mother–infant pairs at 1-month postpartum delivered at a maternal hospital in Tokyo. The main measurements were the presence of mother’s sleep problem, the presence of infant’s unstable sleep quality (hereinafter, unstable sleep), mother’s stimulating activities, such as responding to active sleep immediately, and four indices of mothers’ mental health. After comparing statistically, the basic characteristics and above main measurements with and without infant unstable sleep, a covariance structure analysis was conducted to investigate the association among four main measurements according to the hypotheses made based on previous studies. The infants’ unstable sleep affected the mothers’ sleep problem (β = 0.12), the mothers’ sleep problem affected the stimulating activities (β = 0.11) and the stimulating activities affected the infants’ unstable sleep (β = 0.11). The infants’ unstable sleep and mothers’ sleep problem affected the mothers’ mental health directly (β = 0.20, β = 0.15). The values of GFI (0.993, AGFI (0) and RMSEA (0.032) showed a high fitness of the model. The inter-relationships between the infants’ unstable sleep, mothers’ sleep problem, mothers' stimulating activities, and mothers’ mental health were verified in just 1 month post birth. It is significant that those relationships were obtained in the neonatal periods. The result that mothers’ stimulating activities affect infants’ unstable sleep is important with implications on sleep health education.

Summary The aim of this paper is to describe an uncommon physiological EEG artifact in newborns caused by tongue movements (TM), mimicking anterior slow dysrhythmia (ASD). The subjects are two full-term newborns (39 weeks gestational age (GA)), admitted to the Neonatal Intensive Care Unit for respiratory distress. Both underwent polygraphic video-EEG recording in order to better characterize tremor-like movements of all four limbs that appeared 48 hours after birth. Multichannel video-EEG polygraphy was performed using the 10–20 electrode montage modified for neonates. Ninety minutes of EEG was recorded for each subject, capturing different behavioral states. Background EEG activity was normal for both subjects. During active sleep (AS), synchronous and symmetric slow activity was recorded over bifrontal head regions. For subject 1, bursts of monomorphic 2 Hz delta waves, with an amplitude between 50–100 μV lasting two seconds, were recorded and identified as anterior slow dysrhythmia. For subject 2, polymorphic 1-2 Hz delta waves, 50–100 μV in amplitude and lasting for 20 seconds, were recorded only during suction. After thorough analysis of simultaneous digital video recording synchronized with the EEG trace, this activity was thought to be compatible with glossokinetic artifact. Interpretation of neonatal EEG can be challenging; the background activity is frequently intermixed with physiological artifacts, such as ocular, muscle and movement artifacts, complicating the interpretation. Even continuous video-recording might not make the diagnosis immediately obvious. Therefore, when a rhythmic monomorphic pattern without evolution in amplitude or frequency is seen, we suggest that tongue movement artifact should be considered.

International audience; The objective of the present study was to confirm the link between spontaneous smiling and active sleep in newborns, and to identify the role of the cortex in the generation of spontaneous smiles. A total of 12 healthy newborns born at term and three infants with major congenital abnormalities (two with hydranencephaly and one with a left hemispherectomy) were evaluated by video and polysomnography during a 3-hr sleep period. Smiles were graded and their association with isolated rapid eye movements and grouped rapid eye movements was analysed. In all, 383 smiles were recorded of which 377 occurred during active sleep. Smiles were shown to be significantly associated with active sleep (p

Sleep is important for the development of preterm infants. During sleep, neural connections are formed and the development of brain regions is triggered. In general, various rudimentary sleep states can be identified in the preterm infant, namely active sleep (AS), quiet sleep (QS) and intermediate sleep (IS). As the infant develops, sleep states change in length and organization, with these changes as important indicators of brain development. As a result, several methods have been deployed to distinguish between the different preterm infant sleep states, among which polysomnography (PSG) is the most frequently used. However, this method is limited by the use of adhesive electrodes or patches that are attached to the body by numerous cables that can disturb sleep. Given the importance of sleep, this review explores more unobtrusive methods that can identify sleep states without disturbing the infant. To this end, after a brief introduction to preterm sleep states, an analysis of the physiological characteristics associated with the different sleep states is provided and various methods of measuring these physiological characteristics are explored. Finally, the advantages and disadvantages of each of these methods are evaluated and recommendations for neonatal sleep monitoring proposed.

Introduction and Aims: Current guidelines suggest that oxygen may not be administered to infants with bronchiolitis and SpO2 >90%. However, the pathophysiological consequences of acute hypoxemia in infants are unknown. We hypothesized that even mild nocturnal hypoxemia is associated with increased pulse rate. Methods: Hospitalized infants with bronchiolitis and diurnal SpO2 >90% underwent nocturnal oximetry before discharge. Primary outcomes were: (i) nocturnal average pulse rate; (ii) pulse rate index = [(average pulse rate)-(95th percentile value in active sleep for age)] X 100/ (95th percentile value in active sleep for age). Explanatory variables were: (i) group assignment i.e. bronchiolitis with nocturnal basal SpO2 >90% and Results: Infants with bronchiolitis and hypoxemia (n=24; median age [IQR] 2.6 [1.7-3.6] months) had significantly higher average pulse rate than infants with bronchiolitis and no hypoxemia (n=16; 2.6 [1.7-4.7] months) or controls (n=25; 2.8 [1.6-4.8] months): 138.1±11.8 vs 126.5±13.9 vs 123.4±9.2 bpm; P=.008 and P Conclusion: Infants with bronchiolitis and mild nocturnal hypoxemia have increased pulse rate which decreases after administration of oxygen.

Infant rat pups lacking central nervous system (CNS) serotonin (5-hydroxytryptamine; 5-HT) have unstable breathing during prolonged periods of active sleep. Given that cholinergic neurons are drivers of active sleep and project to respiratory patterning regions in the brainstem, we hypothesized that 5-HT preserves respiratory stability in active sleep by dampening central cholinergic drive. We used whole-body plethysmography coupled with nuchal electromyography to monitor the breathing pattern of 2-wk-old tryptophan hydroxylase 2 ( TPH2)+/+ and TPH2-deficient ( TPH2−/−) pups in active sleep, before and after muscarinic blockade. For the group 1 experiment we injected methylatropine (Ap-M), a CNS-impermeant form of atropine, followed ~30 min later by an injection of atropine sulfate (Ap-S), the CNS-permeant form (both 1 mg/kg, 10 μl bolus iv); both injections occurred within an active sleep episode. We analyzed the effect of each drug on the coefficient of variation of the respiratory period (CV-P) during active sleep. For the group 2 experiment rats were cycled through several episodes of active and quiet sleep before administration of Ap-S (1 mg/kg, 200 μl ip) or vehicle. We assessed the effect of Ap-S on the apnea indices of both genotypes during quiet and active sleep. In group 1 Ap-S significantly reduced the CV-P of TPH2−/− pups ( P = 0.03), an effect not observed in TPH2+/+ pups or following Ap-M. In group 2 the apnea index of TPH2−/− pups was significantly reduced following Ap-S injection ( P = 0.04), whereas the apnea index of TPH2+/+ littermates was unaffected ( P = 0.58). These findings suggest that central 5-HT reduces apnea and stabilizes breathing by reducing cholinergic signaling through muscarinic receptors. NEW & NOTEWORTHY Serotonin in the central nervous system (CNS) is necessary for maintaining the stability of breathing in the early postnatal period, particularly during active sleep. Here we show that the administration of atropine to the CNS selectively stabilizes the respiratory pattern of tryptophan hydroxylase 2-deficient rat pups and reduces their apneas. This suggests that CNS serotonin stabilizes breathing at least in part by reducing central cholinergic drive.

Preterm infants are babies born before completion of 37 w of gestation. Their organs are immature especially brain. Sleep has a vital role in brain development and maturation in infants. Neonatal intensive care unit is a place where infant’s comfort is disturbed by many environmental stimuli. So the sleep is disrupted. Nesting facilitates transformation of sleep pattern from erratic disturbed spells to deep peaceful nights and contented days. This study aimed to investigate the effect of nesting on sleep pattern of infants hospitalized in NICUs. This crossover clinical trial was performed at a tertiary Neonatal Intensive Care Unit (NICU). 21 preterm infants who met the inclusion criteria were enrolled. They were randomly assigned to two groups of nest and routine procedure. Sleep status was evaluated by using neonatal sleep assessment Scale. Duration of Total Sleep Time per cycle (TST) and duration of each stage such as quiet sleep, active sleep indeterminate sleep were recorded and analysed by using paired t-test. Duration of Total Sleep Time per cycle (TST) and duration of each stage were significantly higher among preterm with nesting than usual procedure of care (p

This longitudinal, year-long study compared sleep-wake state organization in two groups of infants-infants whose mothers abused substances during their pregnancies and nonexposed, typically developing, age-matched comparison infants-to determine whether differences in sleep-wake state organization existed between the two groups. Seventeen infants of mothers who were participating in a parent-infant residential treatment program for substance abuse were enrolled. Their sleep-wake state organization over the first year of life was compared to that of 17 age-matched comparison infants. The intent was to follow each infant on five occasions over the first year of life using established methods of time-lapse videosomnography to record sleep-wake state organization: however, attrition in the substance-abusing group was problematic. Some sleep-wake variables (i.e., Active Sleep%, Quiet Sleep%, Awake%, number of nighttime awakenings) were similar for both groups of infants at comparable ages across the first year. Total sleep time and the longest Sustained sleep period (sleep continuity variables) differed significantly at some of the ages measured. Although overall sleep architecture appears highly resilient and well organized, some indications of sleep fragmentation and shortened nighttime sleep periods were observed in the substance-ex posed infants. More research is needed to explain why sleep-continuity variables and not sleep-state proportion variables differed between the two groups.

Aim of this study was to investigate the preferential looking behaviour, subsequent to a familiarization task (8-min) with a previously responsive or motionless face, before and after a sleep cycle. Moreover, the role of the active sleep in memory consolidation of the responsive or motionless faces was explored. Hypotheses were that the newborns undergoing a motionless familiarization will exhibit a novelty effect (preference for the novel face) whereas the newborns undergoing a responsive familiarization will show a familiarity effect (preference for the known face) before and after the sleep cycle; moreover, the amount of active sleep will be associated with the looking time at the known face after a sleep cycle. Forty-five healthy full-term newborns were randomly assigned to two groups (group 1: motionless-familiarization and group 2: responsive-familiarization); in both groups newborns were video-recorded during four post-familiarization face-preference tasks, two of them performed before and two after a sleep cycle. During the pre-sleep-trials, there was not a significant preference for one face in both groups. During the post-sleep trials, the newborns showed a clear preference for the novel face. This effect was more evident in group 1. Only in group 2 there was a significant positive correlation between the active sleep duration and the looking duration at the known-face during the post-sleep trials (r=0.41; p=0.040). Multiple regression confirmed that only in the group 2 the total duration of the active sleep was associated with the looking duration at the known-face during the post-sleep trials (Adjusted R2=0.13; β=0.41; t=2.2; p=0.040). Findings showed that in newborns the face representation can be recalled after a sleep cycle. Moreover, the amount of the active sleep predicted the post-sleep looking toward the known-face only in the newborns who interactively familiarized with the face.

Sleep, the brain and the ability to interact with the environment change a great deal over the first year of life; however, there are no studies on the possible influence of different environmental stimulations on the organization of subsequent sleep–wake cycles in infants. The hypothesis of this study was that greater continuity of contingent tactile stimulation decreases crying behavior, subsequent active sleep (AS) and its fragmentation, and increases smiling behavior and subsequent quiet sleep in newborns. Forty out of the 82 newborns (15- to 30-hr old) of the initial sample satisfied the inclusion criteria and completed the first cycle of sleep during the period between two feedings. The 40 newborns were randomly assigned to four groups after 2′ of baseline observation: continuous stimulation (CS, n = 10); discontinuous nonperiodic stimulation (DnPS, n = 10); discontinuous periodic stimulation (DPS, n = 10); absent stimulation (AbS, n = 10). During baseline measurements, there were no significant differences in crying and smiling behaviors between the four groups, while during the subsequent stimulated wake, the CS group compared to the DnPS group showed more smiling (p

In this prospective, descriptive study, we used a repeated-measures design to explore the 24-hour effects of caregiving and positioning on preterm infants' states and the factors associated with state changes. Thirty preterm infants (gestational age 27.6-36.1 weeks) were observed for 3 days in the neonatal intensive care unit to record six states: quiet sleep (QS), active sleep, transition, active awake, quiet awake, and fussy or crying. The occurrences of QS increased when infants received no caregiving, social interaction, non-nutritive sucking (NNS), and were laterally positioned. However, QS significantly decreased and fussy or crying state increased when infants received routine and intrusive caregiving. These results suggest that caregiving, NNS, and positioning should be appropriately provided to facilitate infants' sleep, and reduce fussiness or crying.

Aim: To evaluate differences in amplitude-integrated electroencephalogram (aEEG) recordings of infants with and without bronchopulmonary dysplasia (BPD). Methods: This is a cross-sectional study of infants ≤27 weeks at birth who did (n = 17) or did not develop BPD (n = 17). aEEG tracings were recorded at 360–366 weeks post-menstrual age for 6 h using the BrainZ BRM3 monitor. A cross-cerebral channel was evaluated using offline software Analyze (BrainZ). Results: Infants with BPD had lower gestational age and higher male predominance (25 ± 1 weeks, 70%) compared with non-BPD infants (26 ± 1 weeks, 30%, all p ≤ 0.03), but similar birth weight (704 ± 195 vs. 796 ± 167 g, p = 0.1). During active sleep, infants with BPD had wider span voltage (p = 0.03), higher lower border voltage (p

OBJECTIVES: Amplitude-integrated electroencephalogram (aEEG) is a valuable tool for the continuous evaluation of functional brain maturation in infants. The amplitudes of the upper and lower margins of aEEGs are postulated to change with maturation and correlate with postmenstrual age (PMA). In this study we aimed to establish reliable reference values of aEEG amplitudes, which provide quantitative guidelines for assessing brain maturation as indicated by aEEG results in neonates and young infants. METHODS: aEEGs from healthy infants (n = 274) with PMAs that ranged from 30 to 55 weeks were divided into 10 groups according to their PMAs. Two 5-minute segments were selected from each aEEG and were used to automatically calculate the upper and lower margins and bandwidths of the aEEG tracings. RESULTS: Interobserver agreement was achieved with an overall correlation of 0.99. The upper and lower margins of the aEEGs in both active and quiet sleep clearly rose in infants after the neonatal period. The bandwidth defined as the graphic distance decreased almost monotonically throughout the PMA range from 30 to 55 weeks. The lower margin of the aEEG was positively correlated with PMA, with a larger rank correlation coefficient during quiet sleep (r = 0.89) than during active sleep (r = 0.49). CONCLUSIONS: Reference values of aEEG amplitudes were obtained for infants with a wide range of PMAs and constituted the basis for the quantitative assessment of aEEG changes with maturation in neonates and young infants. The normative amplitudes of aEEG margins, especially of the lower margin in quiet sleep, are recommended as a source of reference data for the identification of potentially abnormal aEEG results.

Objectives Sleeping newborns display facial mimics which give the impression of negative or positive affects. Smiling and frowning are the simplest and easily recognized. This study is an attempt to understand the neurophysiological meaning of these mimics and to define their connection with the functional role of REM sleep during ontogenesis. Methods Twelve healthy, full term neonates; 3 infants with brain malformations: two hydranencephalics and one with a left hemispherectomy were recorded, for a period of 3 hours during sleep, with the simultaneous use of a polygraphic and a video recording. It was determined during active sleep the frequency of smiling and frowning, their modality of occurrence their distribution within each active sleep. It was calculated for smiling their duration and laterality, their relationship with rapid eye movements and gross body movements. Results In the healthy neonates, 377 smiles and 1039 frownings were analyzed during active sleep. Spontaneous smiling is found to be similar to adult social smiling. Smiles were significantly more intensely expressed on the left side of the face (P Conclusion The data obtained in the healthy neonates and in the pathological infants are compared with the hypotheses of the functional role of paradoxical sleep during ontogenesis.

Objective It has been reported that pacifiers might reduce the risk of SIDS by favouring infants’ arousability from sleep. We evaluated the influence of a pacifier on the frequency and duration of spontaneous arousals in healthy infants. Methods Polygraphic recordings were performed in 14 infants with an age of 51.7 ± 19.9 days (means ± SD) who regularly used a pacifier during sleep. Cortical and subcortical arousals were scored according to the recommendations of the “International Paediatric Work Group on Arousals.” The number of arousals per 10-min-period and the duration of arousals were determined for periods of pacifier use as well as for periods after pacifier dislodgement and were compared with the data of 10 control infants (age 49.8 ± 16.5 days) who never used a pacifier. Results Altogether, 211 arousals in pacifier users and 225 arousals in non-users were scored. In pacifier users, 2.0 ± 1.6 arousals per 10-min-period with a duration of 12.2 ± 3.0 s occurred during pacifier use, and 1.7 ± 1.6 arousals per 10-min-period with a duration of 12.2 ± 3.1 s occurred during periods without pacifier. In pacifier non-users, 2.3 ± 1.2 arousals per 10-min-period (duration 13.9 ± 2.9 s) were scored. The results did not show a significant difference concerning frequency and duration of spontaneous arousals between pacifier users and non-users. Conclusions Our findings suggest that factors other than arousal mechanisms might be responsible for the efficacy of pacifiers in SIDS prophylaxis.

SUMMARY The cyclic patterns of sleep and wakefulness (behavioural ‘states’) were studied polygraphically in a group of 21 normal newborn infants on the first and the fifth days of life. The percentage of time spent awake underwent drastic reduction between the first and the fifth days. The percentage of time spent in state 2 (active sleep) increased correspondingly. The percentage of time spent in state 1 (quiet sleep) remained relatively unchanged; it exceeded state 2 on the first day and was exceeded by state 2 on the fifth day. On the fifth day, there was a tendency for the number of state transitions per hour to be less than on the first day, and for the durations of periods in state 2 to increase. On the first day, infants quite often appeared to wake directly from state 1, but this seldom happened on the fifth day, when waking usually occurred from state 2. Late-clamped infants spent a higher percentage of time in state 1 and less in the quiet awake states than did the early-clamped infants. Individual differences between the lateclamped infants were much greater. Respiratory rate (which is positively related to blood volume in the neonate) was significantly lower in the early-clamped compared with the late-clamped group, in whom the results showed considerable scatter. It is possible that late clamping of the cord represents an additional stress to the neonate and that early clamping confers an advantage on the infant who spends more time awake on the first day, thereby promoting a sound mother and baby relationship. RESUME Un groupe de 21 nouveaux-nes normaux ont eteetudies au ler et 5eme jour de la naissance a l'aide de techniques polygraphiques pour mesurer le pourcentage de temps passe dans les differents etats de vigilance ainsi que la duree des periodes de chacun de ces etats. Le pourcentage de temps passeeveille subit une reduction considerable entre le ler et le 5eme jour. Le pourcentage de temps en stade 2 (sommeil actif) s'accroit d'autant. Le temps passe en stade 1 (sommeil tranquille) demeure inchange, de telle facon qu'il depasse le temps du stade 2 le premier jour et est inferieur le 5eme. Il y a une tendance au 5eme jour a ce que le nombre de changements d'etats par heure soit moindre et que les periodes individuelles de stade 2 s'allongent. Au ler jour, tres souvent, les enfants se reveillent directement a partir du stade 1, mais au 5eme jour, le reveil surveint generalement a partir du stade 2. Les nourrissons a‘clampage tardif’ passent un pourcentage plus eleve de temps au stade 1 et moindre a l'etat tranquille eveille que les enfants a‘clampage precoce’. Les enfants a clampage tardif presentent des variations individuelles beaucoup plus importantes. Le rythme respiratoire qui est relie plus au volume sanguin chez le nouveau-ne est significativement plus lent chez les nourrissons a clampage precocee qu'a clampage tardif, parmi ceux-ci, les resultats presentent une dispersion tres marquee. Il est possible que le clampage tardif du cordon represente une agression supplementaire chez le nouveau-ne et que la clampage precoce confere un avantage en permettant au nourrisson de passer plus de temps eveille le ler jour, ce qui favorise une bonne relation mere-enfant. ZUSAMMENFASSUNG Es wurde eine Gruppe von 21 normaler Neugeborener am 1. und 5. Lebenstag mit polygraphischen Methoden untersucht, um den Prozentsatz der Zeit, die in jedem der verschiedenen Verhaltenszustande verbracht wurde, und die Dauer der einzelnen in ihnen verbrachten Perioden zu messen. Der Zeitanteil des Wachseins erfuhr zwischen dem 1. und 5. Tage eine drastische Verminderung. Der Prozentsatz der Zeit, die im Stadium 2 (aktiven Schlaf) verbracht wurde, stieg entsprechend an. Die Gesamtdauer des Stadium 1 (ruhigen Schlafes) blieb relativ unverandert, so das er am ersten Tage uber den Anteil des Stadium 2 hinausging und am funften Tage hinter ihm zuruckblieb. Es zeigte sich die Tendenz, das die Zahl der Stadienwechsel pro Stunde am 5. Tage geringer war und die Dauer der einzelnen Perioden im Stadium 2 anstieg. Am 1. Lebenstag erwachten die Kindern offenbar ganz haufig direkt aus dem Stadium 1, wahrend sie am 5. Tage gewohnlich aus Stadium 2 erwachten. Die spatabgenabelten Kinder verbrachten einen groseren Prozentsatz ihrer Zeit im Stadium 1 und weniger im ruhigen Wachzustand als die fruabgenabelten Kinder. Die spatabgenabelten Kinder zeigten viel grosere individuelle Unterschiede. Die Atemfrequenz, die dem Blutvolumen beim Neugeborenen proportional ist, war bei den fruhabgenabelten Kindern signifikant niedriger als bei den spatabgenabelten, bei denen die Ergebnisse wiederum eine betrachtliche Schwankungsbreite zeigten. Es ist moglich. das das Spatabnabeln einen zusatzlichen Stress fur das Neugeborene bedeutet und das das Fruhabnabeln von Vorteil ist, da es das Kind am 1. Tage mehr Zeit im Wachzustand verbringen last, was eine intakte Mutter-Baby-Beziehung begunstigt.

SUMMARY Polygraphic methods were used to evaluate the percentage distribution of sleep and awake states and the mean duration of individual periods spent in these states in infants with Down's syndrome, bilirubinaemia and in a heterogeneous group of ‘high-risk’ infants. Not unexpectedly, alterations from previously established normal values were found, as were differences in pattern between the groups. Infants with Down's syndrome spend more time awake at the expense of time in state 2 (active sleep), but prolonged sleep cycles are occasionally possible. Bilirubinaemic infants showed a drastic reduction in the amount of time spent in the awake states. Individual periods spent in state 2 were significantly longer, producing also a prolonged sleep cycle duration. The high-risk group spent abnormally short periods in state 2 and none of the infants studied produced a long sleep cycle. The amount of time spent in awake states varied widely. Anti-epileptic drugs induced more and longer individual periods of state 1 (quiet sleep) at the expense of state 2. The pathophysiological mechanisms behind these alterations in the state cycle are discussed. RESUME Cycles de niveaux de vigilance chez les nouveaux-nes anormaux Grâce a des methodes polygraphiques, trois groupes de nourrissons de conditions anormales ont eteetudies pour evaluer le pourcentage de temps passe dans chacun des divers etats de sommeil et d'eveil ainsi que la duree des periodes individuelles passees dans ces differents etats. Comme on pouvait s'y attendre des differences ont ete observees non seulement par rapport aux valeurs etablies anterieurement mais aussi avec les trois groupes. Les mongoliens passent plus de temps eveilles aux depens du temps passe en stade 2 (sommeil actif), mais des cycles prolonges de sommeil ont pu etren otes occasionnellement. Les nourrissons hyperbilirubinemiques ont montre une reduction considerable du temps passe dans les etats de veille. Les periodes individuelles en stade 2 etaient significativement allongees et de ce fait, les plus longs cycles de sommeil etaient egalement allonges. Le groupe heterogene des nourrissons a `hauts risques' presentait des periodes anormalement courtes en stade 2 et en aucun cas, il n'a ete enregistre de longs cycles de sommeil. La quantite de temps passe en etat de veille variait considerablement. Les medications anti-epileptiques provoquaient un accroissement en nombre et en duree des periodes de stade 1 (sommeil tranquille) aux depens des periodes du stade 2. Les mecanismes physio-pathologiques sous jacents a ces alterations des cycles de vigilance sont discutes. ZUSAMMENFASSUNG Verhaltenszustandszyklen bei abnormen Neugeborenen Drei Gruppen von Kindern mit abnormen Bedingungen wurden mit polygraphischen Methoden untersucht, um den Prozentsatz der Zeit, die sie in jedem der verschiedenen Schlaf- und Wachzu-stande verbringen, und die Dauer der einzelnen Perioden dieser Zustande zu berechnen. Erwartungsgemas fanden sich Unterschiede nicht allein von fruher festgestellten Werten, sondern auch zwischen den drei Gruppen. Die Kinder mit Down-Syndrom verbrachten mehr Zeit im Wachzustand auf Kosten der Zeit des Stadium 2 (aktiven Schlafes), doch wurden gelegentlich auch verlangerte Schlafzyklen gefunden. Die Kinder mit Bilirubinaemie zeigten eine betrachtliche Verminderung der Zeitdauer, die im Wachzustand verbracht wurde. Einzelne Perioden im Schlafstadium 2 waren signifikant verlangert und als Ergebnis dessen war der langste Schlafzyklus auch verlangert. Die heterogene Gruppe der ‘high risk’ Kinder zeigte abnorm kurze Perioden im Schlafstadium 2, und in keinem Fall wurde ein langerer Schlafzyklus festgestellt. Die Zeitdauer des Wachzustandes variierte betrachtlich. Antiepileptische Medikamente verursachten grosere Mengen und langere Einzelperioden des Stadium 1 (vuhigen Schlafes) auf Kosten des Stadium 2. Die pathophysiologischen Mechanismen dieser Veranderungen im Zustandszyklus werden diskutiert.

The reptile Iguana iguana exhibits four states of vigilance: active wakefulness (AW), quiet wakefulness (QW), quiet sleep (QS) and active sleep (AS). Cerebral activity decreases in amplitude and frequency when passing from wakefulness to QS. Both parameters show a slight increase during AS. Heart rate is at a maximum during AW (43.8+/-7.9 beats/min), decreases to a minimum in QS (25.3+/-3.2 beats/min) and increases in AS (36.1+/-5.7 beats/min). Tonical and phasical muscular activity is present in wakefulness, decreases or disappears in QS and reappears in AS. Single or conjugate ocular movements are observed during wakefulness, then disappear in QS and abruptly reappear in AS. Although these reptiles are polyphasic, their sleep shows a tendency to concentrate between 20:00 and 8:00 h. Quiet sleep occupies the greater percentage of the total sleep time. Active sleep episodes are of very short duration, showing an average of 21.5+/-4.9 (mean+/-SD). Compensatory increment of sleep following its total deprivation was significant only for QS. Reaction to stimuli decreased significantly when passing from wakefulness to sleep. It is suggested that the lizard I. iguana displays two sleep phases behaviorally and somatovegetatively similar to slow wave sleep and paradoxical sleep in birds and mammals.

Objective To further understand state development of preterm infants throughout hospitalization and the effects of selected infant characteristics on state development. Design Secondary data analysis of a 2-group, experimental design study. Setting Two nurseries in a Northwest medical center. Participants Ninety-seven hospitalized, medically stable, preterm infants. Fifty-one subjects were females. Methods Two hundred and eighty-five real-time video recordings of infants performed during 4 hour interfeeding intervals. Sleep-wake states were coded at 15 second intervals. Results Active sleep was the dominant state across postmenstrual ages. Although not statistically significant, preterm infants showed developmental changes in state organization with increased quiet sleep, drowsy, and awake, decreased active sleep, and more defined and less diffuse states over age. A significant gender effect was found, with males having less active sleep ( p =.012), more drowsy ( p =.03), more awake ( p =.043), less defined ( p =.002), and more diffuse ( p =.001) states compared with females. Conclusion The predominance of active sleep during the preterm period reflects level of brain maturation. The results emphasize individual variations in state organization influenced by endogenous and environmental factors. Gender differences are potential sources of individual variation.

Cardio Respiratory Coupling (CRC) plays a key role during infant development. Nonetheless, mechanisms underlying it are still mostly unexplained and tools to assess it are often inadequate to understand its functioning. This study aims to evaluate the feasibility of CRC activity detection and quantification analyzing ECG and respiration of newborn healthy subjects. Cross-spectral analysis (coherence) and a novel application of a nonlinear method (Bivariate Phase Rectified Signal Averaging) were applied on 10 minutes recording from 4 subjects. Our preliminary results show that these methods can provide significant information about the occurrence and the strength of CRC, opening interesting perspectives in the evaluation of cardiorespiratory pathologies in newborn infants. In particular, the observed dynamic behavior appears stable and centered around one single frequency in Quiet Sleep, while being more variable and less consistent in Active Sleep.

This article aims at summarizing normal EEG criteria and their maturational pattern in premature infants of 24 to 30 weeks gestational age. Although very premature infants with a normal outcome are not numerous, their normal EEG patterns must be known, as EEG constitutes a basis for neurological prognosis. Background activity is first discontinuous. Discontinuity decreases thereafter with increasing age, so that some long periods of continuous activity may be observed in active sleep, around 30 weeks of age. Conversely, interburst intervals become shorter and the proportion of time without EEG activity is decreasing. Based on EEG activity and eye movements, a rough sleep-state differentiation was described as soon as 25 weeks of gestational age and is completely achieved at 30 weeks. The main EEG figures are high-voltage delta waves of higher amplitude and slower frequency in younger infants. Temporal delta waves occur in sequences, these are very characteristic of the very premature infant; thereafter, they become smaller, less numerous and eventually disappear around 27-28 weeks. In contrast, occipital delta waves remain numerous and of high voltage, are usually bilateral and superimposed with fast rhythms. The two types of frontal delta waves that are observed in 24-27 weeks prematures disappear with maturation. Bursts of synchronized delta waves are less numerous than localized delta waves and also disappear before 28 weeks of age. Finally, diffuse theta bursts are mainly recorded at 26-27 weeks GA and become more localized in temporal areas with maturation. At 30 weeks, they are observed on temporal areas, mainly during slow-wave sleep.

Objective : To test the discriminatory topographic potential of a new method of the automatic EEG analysis in neonates. A quantitative description of the neonatal EEG can contribute to the objective assessment of the functional state of the brain, and may improve the precision of diagnosing cerebral dysfunctions manifested by ‘disorganization', ‘dysrhythmia' or ‘dysmaturity'. Methods : 21 healthy, full-term newborns were examined polygraphically during sleep (EEG-8 referential derivations, respiration, ECG, EOG, EMG). From each EEG record, two 5-min samples (one from the middle of quiet sleep, the other from the middle of active sleep) were subject to subsequent automatic analysis and were described by 13 variables: spectral features and features describing shape and variability of the signal. The data from individual infants were averaged and the number of variables was reduced by factor analysis. Results : All factors identified by factor analysis were statistically significantly influenced by the location of derivation. A large number of statistically significant differences were also established when comparing the effects of individual derivations on each of the 13 measured variables. Both spectral features and features describing shape and variability of the signal are largely accountable for the topographic differentiation of the neonatal EEG. Conclusions : The presented method of the automatic EEG analysis is capable to assess the topographic characteristics of the neonatal EEG, and it is adequately sensitive and describes the neonatal electroencephalogram with sufficient precision. Significance : The discriminatory capability of the used method represents a promise for their application in the clinical practice.

Neonatal electroencephalography (EEG) presents some of the most difficult challenges in EEG interpretation. It differs significantly in many ways from EEG of older children and adults. Technologically, acquisition of a neonatal EEG is significantly more difficult and different than an adult EEG. There are numerous features that are age-specific and change almost week-to-week in the preterm infant. Some features may be normal at one age and abnormal if they persist for several weeks. Many of these features also have different implications in neonates as compared to older individuals. These issues mandate a different approach to neonatal EEG interpretation. In this article an overview of neonatal EEG is presented. After a brief discussion of relevant technical issues, various normal EEG features encountered in neonates are discussed. This is followed by a discussion of the ontogeny of EEG, starting from the age of viability to the first few months of life. A description of various abnormalities follows. Finally, an approach to analysis of a neonatal EEG is presented.

STUDY OBJECTIVES To determine the total number of active sleep laboratories in the United States and the number of polysomnograms conducted on a yearly basis in these laboratories. METHODS All members of the AASM and all AASM accredited sleep laboratory directors received a questionnaire addressing their laboratory and its volume. In three states, multiple telephone calls to AASM members were used to correctly identify the absolute number of labs and their PSG volume in those states. Extrapolating from the number of labs studies identified per questionnaire relative to the correct number (per calls) in those states and, then applying this ratio to the entire US, the total number of labs and studies was determined. RESULTS Our data suggests that there are, in the year 2001, 1,292 sleep laboratories conducting 1,165,135 polysomnograms per year. This comes to 427 PSG's/year per 100,000 population in the United States. CONCLUSIONS These data suggest that there are a relatively large number of sleep laboratories in the US conducting a substantial number of PSG's. However, there was considerable variability in this volume between states that did not relate to known markers of healthcare utilization. These numbers have likely increased since 2001.

Aim of this study is to evaluate the relationships between a new classification of somatosensory-evoked-potentials in cascade (SEPs-C) with simultaneous video-electroencephalogram (VEEG) obtained by 1-h integrated neurophysyiological monitoring (1 h-IMNA) and clinical assessment by Sarnat–Sarnat (SS), Cerebral arteries Resistance-Index (RI) using pulsed-Doppler and Magnetic Resonance Imaging (MRI) as early predictors of a 1-year outcome in Hypoxic-ischemic-encephalopathy (HIE). 1 h-IMNA of VEEG and SEPs (bilateral median nerve stimulation) were assessed in 8 (4M-4F) asphyxiated term-infants within 1 and 4 weeks from birth. In all infants SS, RI and MRI were early performed. 1 h-IMNA and RI were also assessed in 20 healthy term-infants, as control-group. Trend of SEPs-C was evaluated in relation to behavioural-states during the VEEG-recording (wakefulness, quiet/active sleep). In control-group SEPs-C were present and modulated. In the 8 asphyxiated infants were identified 4 cortical SEPs’ patterns: bilateral absence/pathological-alteration (A–A), monolateral absence/pathological alteration (A–N), hypovoltated/non-modulated (h/nm), normal (NN) in agreement with RI and MRI. The recognize of SEPs-C pattern during 1 h-IMNA, considering hypovoltage and/or modulation in relation to behavioural-state, especially if concording with RI and MRI’s patterns, could implement the early prognostic-value to identify the moderate asphyxiated newborns. This proposal of neonatal SEPs’classification and its relations with IR and RMI call for further studies as early predictors of HIE, especially if mild.

Background and purpose The aim of the present study was to verify whether the proposed method of computer-supported EEG analysis is able to differentiate the EEG activity in quiet sleep (QS) from that in active sleep (AS) in newborns. A quantitative description of the neonatal EEG may contribute to a more exact evaluation of the functional state of the brain, as well as to a refinement of diagnostics of brain dysfunction manifesting itself frequently as ‘dysrhythmia' or ‘dysmaturity'. Patients and methods Twenty-one healthy newborns (10 full-term and 11 pre-term) were examined polygraphically (EEG—eight channels, respiration, ECG, EOG and EMG) in the course of sleep. From each EEG record, two 5-min samples (one from QS and one from AS) were subject to an off-line computerized analysis. The obtained data were averaged with respect to the sleep state and to the conceptional age. The number of variables was reduced by means of factor analysis. Results All factors identified by factor analysis were highly significantly influenced by sleep states in both developmental periods. Likewise, a comparison of the measured variables between QS and AS revealed many statistically significant differences. The variables describing (a) the number and length of quasi-stationary segments, (b) voltage and (c) power in δ and θ bands contributed to the greatest degree to the differentiation of EEGs between both sleep states. Conclusion The presented method of the computerized EEG analysis which has good discriminative potential is adequately sensitive and describes the neonatal EEG with convenient accuracy.

The multichannel electroencephalograph (EEG) of six healthy term neonates was recorded during awake as well as during active and quiet sleep. The existence and nature of the interdependencies among the different brain areas were studied by means of a multivariate variant of the surrogate data method. Such interdependencies were then quantified by using the coherence function and a newly developed non-linear index. The results showed that during quiet sleep these interdependencies were mostly non-linear, asymmetric and greater than those found during both awake and active sleep. We conclude that the index might be useful to define patterns of EEG interdependencies in healthy neonates, thereby allowing the early detection of brain dysfunctions.

Background : Electrophysiological and behavioral studies have shown that stimulus relevance contributes to auditory processing in sleep and auditory stimuli changes the sleep stages. So we observed changes in auditory processing due to sleep stages by recording infant mismatch negativity (MMN) during different states and investigated the arousal mechanisms. Methods : Auditory event-related potentials (ERPs) of 26 neonates were recorded using high-density EGI EEG system. Stimuli consisted of 1000Hz tones with 90% probability as standard and 1200Hz with 10% probability as deviant. Study 1 was designed for the confirmation of the recording of MMN from neonates and Study 2 for investigating whether an appropriate stimulus onset asynchrony (SOA) of the stimulus would induce a clear difference in the latency or amplitude. Results : (Study 1) MMN were obtained from all subjects. No differences of the latencies, amplitudes and distribution due to arousal or sleep stage were observed. After the MMN response occurred, a prominent negativity like Nc was seen in response to deviant stimuli in active sleep and waking state. (Study 2) No distinct differences between the difference states were seen in any SOA. Conclusions : Only MMN did not characterize the arousal or sleep stage. But the modality of the auditory evoked potentials (AEPs) may differ according to the state, so further detailed investigation could enable the detection of the infants' state using the AEP.

To assess the manner in which between-sleep state transitions occur in infants, we examined polysomnography (PSG) studies in 25 clinically and neurologically normal, appropriate-for-gestational-age, 30-to-36-week-gestational age (GA) infants. Twenty infants underwent paper PSG and five infants digitised PSG. Sleep states were coded based on concordance of REMs and the electroencephalogram (EEG) pattern. Data were analysed using a multivariate linear model, with the subject factor as a cluster. Duration of active sleep (AS) to quiet sleep (QS) transitions (median 4.8 min) was significantly longer than duration of QS to AS transitions (1.7 min) and was independent from GA and from the recording method (paper vs. digitized PSG). The sequence of modifications in parameters (REM and EEG) was invariable: REM cessation was the first change in AS to QS transitions, and REM appearance was the last change in the QS to AS transitions. Our study demonstrates a stable, well-organized pattern of between-sleep-states transitions in healthy 30-to-36-week GA premature infants. These findings are similar to those described in full-term newborns and are in agreement with our previous observations of well-defined sleep states at the age investigated here.

The purpose of this study was to evaluate the effects of a gentle human touch (GHT) intervention provided to 42 preterm infants (27-33 weeks gestational age), for 10 min, three times daily for 10 days. There was no significant difference in mean HR levels or in percent of abnormal heart rate (HR) or O2 saturation comparing 10-min baseline (B), GHT, and 10-min post-touch (PT) phases. There were significantly lower levels of active sleep, motor activity, and behavioral distress during GHT compared to B and P phases. There were no differences among the 42 infants in the GHT group and 42 infants in a randomly assigned control group on any outcome variable including weight gain, morbidity status, or behavioral organization. The findings suggest that GHT generally is a safe and soothing type of touch to provide to young preterm infants, but that individual infant responses to touch need to be continuously monitored by NICU staff and parents.

Although thermoregulation and sleep exhibit gender differences in adults, the question is still debated in neonates. The aim of this study was to examine the relationship between gender-related sleep differences and cool defence mechanisms in neonates. Sleep and thermoregulation were recorded in healthy preterm neonates (21 boys and 17 girls, 37 +/- 2 weeks post-conceptional age) exposed to thermoneutral and cool conditions. Sleep was analysed for continuity and structure. Although the cool exposure did not strongly impair body homeothermia, sleep was altered but without any significant gender difference. However, when data recorded under each of the thermal conditions were pooled, some gender differences emerged: boys slept less, with more wakefulness after sleep onset, more active sleep and less quiet sleep than girls. In contrast to sleep architecture, most of the sleep continuity parameters exhibited greater variability in boys than in girls. This variability may bias the statistical analyses and probably explains the varying conclusions reported in the literature regarding gender-specific sleep-related differences.

Direct behavioral observation and motility monitoring procedures provide reliable data, and both are appropriate for sleep/wake state measurements starting immediately after birth. Using these procedures, newborn rats, rabbits, and humans were found to have a greater amount of quiet sleep on the day of birth rather than 24 hr later. Changes in active sleep and wake were inconsistent across the 2 days. The quiet sleep findings are contrary to the developmental course which increases with age. The findings are interpreted as a temporary adaptive response to the stress of the birth process.

To assess the effects of sleep state on human retinal electric responses, full-field electroretinograms were obtained in a cross-sectional study from 123 preterm infants at 36, 40 and 56 weeks of post-gestational age. At each age, electroretinographic recordings were assigned to one of two groups according to whether the infants were in active sleep or quiet sleep. Both sleep states were determined behaviorally. Pure rod, maximal, 30 Hz flicker and light adapted single cone responses were evaluated when a sleep state was clearly established. Peak-to-peak amplitudes of most electroretinographic responses were significantly larger in active sleep relative to quiet sleep at 36 and 40 weeks of post-gestational age. We speculate that larger amplitudes during active sleep may play a role in the maturation of the visual system.

The development of temporal organization of sleep–wake states during the preterm period was examined. Seventy-one high-risk preterms from two cohorts were observed from 7 to 11 p.m. weekly from the time they were no longer critical until discharge. Mixed general linear model analyses found that with increasing postconceptional age, quiet waking, active waking, and sleep–wake transition bouts occurred more frequently, quiet sleep bouts occurred less frequently, and active waking and quiet sleep bouts increased in length. However, these developmental patterns were not stable over cohorts. On the other hand, the transitional probabilities between states were similar in both cohorts, providing evidence for biological bases for some aspects of temporal organization. Active sleep was pivotal in state transitions. Younger infants showed fewer transitions that did not involve active sleep. Thus, temporal organization is an early characteristic of sleep–wake states but is not a unitary phenomenon. Transitional probabilities remain relatively invariant, whereas bouts lengths and frequencies may be altered in different populations or by differing environmental conditions. © 1998 John Wiley & Sons, Inc. Dev Psychobiol 33: 257–269, 1998

Objective: An investigation was made of how postnatal maturation of cardiac control can be described by linear and non-linear methods of time series analysis. Methods: Sixteen healthy and term newborns were studied during their first 6 months of life. Power spectrum analysis including total power (TP), low frequency power (LF), high frequency power (HF) and LF/HF ratio were performed on the instantaneous heart rate (IHR) time series and mean heart rate (HR) was derived. The largest Lyapunov exponent (LLE) was calculated using a modified Wolf algorithm and checked by means of the surrogate-data test. Results: There is an age dependency for the parameters LLE, HR, TP, HF, LF, LF/HF for active and LLE, HR, TP, HF, LF/HF for quiet sleep. HR is characterised by a steep increase between the 5th and 7th day. HF demonstrates a distinct development with high values around the first week and 90–180th day and low values around the 10–60th day. TP, LF and LF/HF show significantly higher values in active sleep in comparison to quiet sleep. For all ages and sleep stages, positive LLE were found, indicating sensitivity to initial conditions, a hall-mark of chaos. For the period between the 7 and 90th days of life, the LLE for active sleep took on larger values compared with the LLE of quiet sleep. Conclusions: This study shows that by linear as well as non-linear analysis one can reveal the complexity of the IHR development in humans and may gain insight into the system controlling the heart during the period considered. The positive LLE indicate that there is a non-linear component in the heart rate control. There is no “straight line” development for the parameters analysed within the first 6 months. This may result from manifold influences on the autonomic system, due to structural and functional maturation in this period of life.

Background: This study is concerned with the changes of electroencephalographic (EEG) from immature neonatal to the development of mature normal EEG pattern with special attention given to the infant’s age (0–12 months), growth, and developmental level. Aims and Objectives: The objective is to study serially development of specific EEG patterns in infants, i.e., from birth to 12 months of age. Materials and Methods: This is a longitudinal follow-up study conducted on 50 (27 female and 23 male) healthy, normal, full-term infants delivered vaginally in the Department of Obstetrics and Gynaecology, Netaji Subhash Chandra Bose, Medical College and Hospital, Jabalpur, Madhya Pradesh, starting from the birth to 12 months of age in normal environment in the Department of Physiology EEG-unit for 60 min in 5 different visits, i.e., at birth/0–2 week, 3-month, 6 months, 9 months, and 12 months. Result: This study provides clearly established strong changes in EEG wave pattern and their appearances with increased speed of response, which are most clearly visible from the time of birth, 3–6 months, and at 12 months of age. These marked changes of EEG may be associated with language and other motor milestone development. Conclusion: Sleep characteristics during this period may have predictive value in the assessment of future neurodevelopmental conditions. The study also concluded that the percent of time that infants spend in sleep decreased sharply from 3 to 6 months, but the sleep cycle becomes more defined. The duration of infant’s sleep did not change significantly across the 1st year, but the percent of time spent in active sleep is markedly decreased, i.e., ≤25%, and the sleep progresses toward maturity which is confirmed by the establishment of continuity, symmetrical synchronous EEG pattern, and the disappearance of neonatal trace alternant, along with the focusing on measurement of weight and head circumference.

Objective: to analyze the full-term newborn’s readiness to suck the mother’s breast in the first breastfeeding in rooming-in. Methods: analytical, quantitative study with 43 full-term newborns. Results: the states of sleep and wakefulness prevailing before breastfeeding were 41.9% alert and quiet during breastfeeding, 48.8% active sleep. In all domains assessed in the conduction of breastfeeding, the favorable signs had the highest percentage: Body posture (85.6%); Newborn responses (82.3%); Emotional bond (73.8%); Breast anatomy (100.0%); Suction by the newborn (86.1%); Time spent in the suction (78.4%). The average of the breastfeeding time was 12.08 minutes. Conclusion: full-term newborns showed good readiness to suck maternal breast in the first breastfeeding, since they prevailed in active state, showed good frequency of suction and in the conduction of breastfeeding, most of the signs were favorable to it. Objetivo: analisar a prontidão do recém-nascido a termo para sugar a mama materna na primeira mamada em alojamento conjunto. Métodos: estudo quantitativo, analítico, realizado com 43 recém-nascidos a termo. Resultados : os estados de sono e vigília predominantes antes da mamada foram: 41,9% alerta quieto e, durante mamada, 48,8%, sono ativo. Em todos os domínios avaliados na condução da mamada, os sinais favoráveis apresentaram o maior percentual: Postura corporal (85,6%); Respostas do recém-nascido (82,3%); Vínculo emocional (73,8%); Anatomia da mama (100,0%); Sucção do recém-nascido (86,1%); Tempo gasto na sucção (78,4%). A média do tempo da mamada foi de 12,08 minutos. Conclusão: recém-nascidos a termo apresentaram boa prontidão para sugar a mama materna na primeira mamada, uma vez que prevaleceram em estado ativo, apresentaram boa frequência de sucção e, na condução da mamada, a maioria dos sinais apresentou-se favorável a ela.

The aim of this study was to examine the validity of activity-based monitoring (actigraphy) for the assessment of sleep-wake patterns during the 1st year of life. Forty-one infants were directly observed for sleep-wake state determination by trained observers. Concomitant activity data obtained by actigraphs attached to the infants' ankles during the observation were matched on a minute-by-minute basis, and a scoring algorithm was developed for automatic identification of sleep-wake states. Overall, the automatic scoring algorithm for activity data reached 95.3% agreement rate with the observers' sleep-wake scoring. Distinction of quiet and active sleep reached agreement rates ranging from 54% to 87% at different ages. Significant night-to-night stability was found for several derived sleep-wake measures, and high variability was noted for other measures. It is concluded that actigraphy provides valid sleep-wake measures during the 1st year of life.

Five physiologic groupings of 45 EEG-sleep measures were acquired from serial 24-channel EEG-sleep recordings (i.e., sleep architecture, continuity, EEG spectral, phasic, and autonomic measures), utilizing 129 studies on 56 healthy preterm infants from 28 to 43 weeks postconceptional age (PCA) who were neurodevelopmentally normal on follow-up. Regression analyses chose the least number of measures that best reflected maturation. Four of 45 variables (i.e., spectral alpha energy during quiet sleep, total spectral EEG energy, arousal number during active sleep, and percentage of EEG discontinuity) most significantly explained brain maturation in neonates36 weeks PCA. Three of 45 variables (i.e., spectral theta and beta energies during active sleep and spectral alpha energy during quiet sleep) were most representative after 36 weeks PCA. Spectral EEG energies were the strongest indicators of maturation compared with other measures, particularly in near-term neonates.

Thirty-five healthy, premature infants, ranging from 30–39 weeks postconceptional age, were observed continuously for 6 to 24 hr. Behavioral state and electroencephalographic patterns were coded for each minute. Using these data, three questions regarding coding of states of sleep were addressed: What is the concordance between behavioral codes and specific EEG patterns? Does the concordance between behavioral codes and EEG patterns change with postconceptional age? What range of error can be expected when observation periods shorter than 24-hr are used to estimate the daily distribution of quiet sleep (QS) and active sleep (AS)? With behavioral codes as the standard, concordances of EEG patterns for QS and AS were 72.5 and 92.1% respectively. With EEG patterns as the standard, behavioral codes for QS and AS agreed 83.0 and 88.9%. Agreement between behavioral codes and EEG patterns for QS increased with age. Finally, variation in estimates of the daily distribution of QS and AS decreased dramatically as the length of observation increased from 3 to 24 hr. © 1995 John Wiley & Sons, Inc.

The sleep/wake states of 20 premature and 22 fullterm infants were compared from 24-hour recordings obtained in the home. Using a nonintrusive home monitoring system, they were recorded once a week when they were 1 to 5 weeks postterm. Significant individual differences were found for both groups for all measures obtained. Developmental changes in Active Sleep and Quiet Sleep were found in both groups. Both groups showed more Waking during the day and more of the two sleep states at night. Both groups showed ultradian cyclicity from the first postterm week. The groups did not differ with respect to stability of their sleep patterns over weeks. However, the premature infants had more Quiet Sleep, longer Quiet Sleep bouts, and less Active Sleep, The state differences suggest a more uneven developmental course for states in prematures, and this may reflect compromise in their Central Nervous System status as a consequence of perinatal and early postnatal stress.

Spontaneous movements of premature infants between 25 and 34 weeks conceptional age were observed for 1 hr on two or three occasions. Subjects had low-risk prognoses and were clinically stable at the time of testing. Behavioral acts were scored using a 0/1 time sampling technique in 60 continuous, 1-min time blocks. Temporal associations between individual movements were found using chi-square analyses. Some associated behaviors contained combinations consistent with neonatal action patterns, for example, single and bilateral leg kicking, head turning, and mouthing. Features of state organization were also evident in that general motor activity (GM), which has been used as a marker of active sleep (AS) in neonates, was found to cluster temporally with startle, facial, and head movements but not eye movements. Behavioral quiescence (> or = 5 s) was dissociated from AS-related behaviors (GM, facial, head, and eye movements). Combinations of state-segregated behaviors were more likely to exhibit co-occurrence within 1-min intervals in infants 30 weeks conceptional age and older.

Many studies have shown a greater frequency of apneas in active sleep than in quiet sleep in healthy newborns and infants, both full-term and preterm. The ontogeny of increased apnea during active sleep is related to phasic inhibitory-excitatory central mechanisms occurring during active sleep. Respiratory instability in active sleep can be increased by factors which modify the newborn’s or infant’s homeostasis. We have shown: (1) an increase in body temperature (0.8 °C) significantly augments periodic breathing in preterm infants at 40 weeks postconceptional age; (2) maternal administration of meperidine is followed by a significant increase in number of apneas during the first hours of life in full-term newborns, but only during active sleep; (3) sleep deprivation induces significantly more obstructive respiratory events in active sleep than in quiet sleep in infants. Active sleep appears to be a risk period for exaggeration of the occurrence of apneas when the newborn’s or infant’s homeostasis is disturbed.

Respiratory inductive plethysmography (RIP) is a well-accepted noninvasive technology for monitoring breathing patterns in adults. Prior attempts to calibrate this device in babies have been fraught with technical difficulties, thereby limiting applications in this population. Recently, a new method, qualitative diagnostic calibration (QDC), has been shown to provide accurate calibration of tidal volume in adults. The QDC method is based upon principles of the isovolume maneuver and carried out during natural breathing without specialized respiratory maneuvers or postural changes. We calibrated RIP with QDC in the supine posture and compared tidal volume (VT) measured with RIP to VT by a face mask-pneumotachograph (PNT) in 21 healthy full-term newborns in supine and prone postures. Eleven of the babies were calibrated during active sleep and 10 in quiet sleep. The mean VT in the supine and prone postures were 19 and 25 ml, respectively. In the supine and prone postures, weighted mean difference between RIP (VT) and PNT (VT) and 95% confidence intervals were -0.05 ml (-0.27, 0.18) and -0.32 ml (-0.08, 0.55), respectively. There was no difference in the accuracy of RIP relative to PNT calibrated during active sleep when thoracoabdominal incoordination was present or quiet sleep when it was not in either the supine or the prone postures. Therefore, in full-term infants, RIP calibrated with QDC solely in the supine posture provides clinically acceptable measurements of VT in both supine and prone postures.

Neonatal sleep behaviors and behavioral state cycling were observed for 20 pairs of same-sex, fullterm twins in which one twin of the pair was appropriate-for-gestational-age (AGA) and the other twin was small-for-gestational-age (SGA). Time-sampling recordings were made in active sleep of number and vigor of limb movements, body and head movements, and mouth movements. No group differences were observed for time spent in first active sleep, first quiet sleep, or length of first sleep cycle. Examination of specific behaviors indicated a significantly higher incidence of vigorous limb movements and right hand-to-mouth movements, with a trend for more small limb movements and left hand-to-face movements, for AGA twins when compared with SGA twins. SGA twins had significantly more spontaneous smiles and a trend for more spontaneous startles than AGA twins. A stepwise discriminant analysis indicated that a composite of the variables smile, large limb movement, startle, and left hand-to-face significantly discriminated between the two groups, with 90% correct classification of the AGA twins and 75% correct classification of the SGA twins. The results demonstrated the utility of evaluating specific sleep behaviors, rather than state cycling only, to describe differences in neonatal sleep characteristics between AGA and SGA twins.

The present paper investigates the neural ontogeny of newborns in view of electroencephalogram (EEG) complexity during active sleep (AS) and quiet sleep (QS). Sample entropy (SampEn) is applied to EEG recordings from 168 newborns with postmenstrual age (PMA) ranging from 25 to 60 weeks. The relationship between neurodevelopment and PMA is then explored according to the statistical analysis of the median and interquartile range of SampEn curves. It is found that SampEn of EEG during AS is higher than that during QS. SampEn increases during both AS and QS before about 42 weeks in PMA while it ceases its increase in QS and even decreases in AS after newborns reaching term age. A distinct decrease in the interquartile range of SampEn is found with increasing PMA (from 25 to about 50 weeks), followed by maintenance of low fluctuation in SampEn curves. The study in this paper sets the stage for exhaustive investigation of the SampEn of EEG during brain maturation in newborns. And it could be hoped that SampEn in sleep EEG might be a useful parameter against which delays and aberrations in brain maturation might be tested. The SampEn changes during brain maturation also offer functional clues about neurodevelopment, based on which further explorations could be done. The significance of this paper is the discovery of the decrease in EEG complexity after newborns reaching term. Although some potential neurophysiologic reasons are given, this new discovery might require more study to investigate. In addition, the fluctuation of EEG complexity is analyzed for the first time, which helps to understand the EEG maturation in neurodevelopment.