Infants' neural sensitivity to social interactions varies by income and infant-directed speech.

Social interactions are essential for infant brain development, yet we know little about how infant functional connectivity differs between social and nonsocial contexts, or how sensitivity to differences between contexts might be related to early distal and proximal environmental factors. We compared 12-month-old infants' intrahemispheric electroencephalographic (EEG) coherence between a social and a nonsocial condition, then examined whether differences between conditions varied as a function of family economic strain and two maternal behaviors at 6 months, positive affect and infant-directed speech. We found lower EEG coherence from the frontal region to the central, parietal, temporal, and occipital regions during the social condition, but only for infants from higher-income families and infants whose mothers used higher proportions of infant-directed speech.

Family nurture intervention increases term age forebrain EEG activity: A multicenter replication trial.

Objective: This trial (RCT-2) sought to replicate the EEG findings of a randomized controlled trial of Family Nurture Intervention in the NICU (FNI-NICU) (RCT-1) comparing infants receiving standard care (SC) with infants receiving SC plus FNI .

Methods: RCT-2 (NCT02710474) was conducted at two NICUs. Subjects were randomly assigned to receive SC or FNI during their NICU stay.

Family nurture intervention alters relationships between preterm infant EEG delta brush characteristics and term age EEG power.

Objective: Family Nurture Intervention (FNI) facilitates mother/infant emotional connection, improves neurodevelopmental outcomes and increases electroencephalogram (EEG) power at term age. Here we explored whether delta brushes (DB), early EEG bursts that shape brain development, are altered by FNI and mediate later effects of FNI on EEG.

Methods: We assessed DB characteristics in EEG data from a randomized controlled trial comparing infants with standard care (SC, n = 31) versus SC + FNI (n = 33) at ~35 and ~40 weeks GA.

Integrated information in the EEG of preterm infants increases with family nurture intervention, age, and conscious state.

A putative quantifier of consciousness, integrated information, was applied to preterm infant EEG data after novel pre-processing. Integrated information had a non-random structure as a function of the time lag over which it was computed. For most lags, it increased with age in early life, but even more so in infants exposed to Family Nurture Intervention (FNI), providing further evidence that FNI advances brain maturation in preterm infants.

Family nurture intervention in preterm infants increases early development of cortical activity and independence of regional power trajectories.

Aim: Premature delivery and maternal separation during hospitalisation increase infant neurodevelopmental risk. Previously, a randomised controlled trial of Family Nurture Intervention (FNI) in the neonatal intensive care unit demonstrated improvement across multiple mother and infant domains including increased electroencephalographic (EEG) power in the frontal polar region at term age. New aims were to quantify developmental changes in EEG power in all brain regions and frequencies and correlate developmental changes in EEG power among regions.

Maternal cortisol slope at 6 months predicts infant cortisol slope and EEG power at 12 months.

Physiological stress systems and the brain rapidly develop through infancy. While the roles of caregiving and environmental factors have been studied, implications of maternal physiological stress are unclear. We assessed maternal and infant diurnal cortisol when infants were 6 and 12 months.

A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG.

Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants socially interact. Electroencephalography (EEG) power is an advantageous technique to assess infant functional neural activation. However, many studies record infant EEG only during one baseline condition.

Vital signs and their cross-correlation in sepsis and NEC: a study of 1,065 very-low-birth-weight infants in two NICUs.

Background: Subtle changes in vital signs and their interactions occur in preterm infants prior to overt deterioration from late-onset septicemia (LOS) or necrotizing enterocolitis (NEC). Optimizing predictive algorithms may lead to earlier treatment.

Methods: For 1,065 very-low-birth-weight (VLBW) infants in two neonatal intensive care units (NICUs), mean, SD, and cross-correlation of respiratory rate, heart rate (HR), and oxygen saturation (SpO) were analyzed hourly (131 infant-years' data).

Variation in infant EEG power across social and nonsocial contexts.

To understand the infant social brain, it is critical to observe functional neural activation during social interaction. Yet many infant electroencephalography (EEG) studies on socioemotional development have recorded neural activity only during a baseline state. This study investigated how infant EEG power (4-6Hz and 6-9Hz) varies across social and nonsocial contexts.

Toward an electrocortical biomarker of cognition for newborn infants.

The event-related potential (ERP) effect of mismatch negativity (MMN) was the first electrophysiological probe to evaluate cognitive processing (change detection) in newborn infants. Initial studies of MMN predicted clinical utility for this measure in identification of infants at risk for developmental cognitive deficits. These predictions have not been realized.

Anesthetic-specific electroencephalographic patterns during emergence from sevoflurane and isoflurane in infants and children.

Background: Devices that monitor the depth of anesthesia are increasingly used to titrate sedation and avoid awareness during anesthesia. Many of these monitors are based upon electroencephalography (EEG) collected from large adult reference populations and not pediatric populations (Anesthesiology, 86, 1997, 836; Journal of Anaesthesia, 92, 2004, 393; Anesthesiology, 99, 2003, 34). We hypothesized that EEG patterns in children would be different from those previously reported in adults and that they would show anesthetic-specific characteristics.

EEG functional connectivity in term age extremely low birth weight infants.

Objective: The hypothesis is tested that electrocortical functional connectivity (quantified by coherence) of extremely low birth weight (ELBW) infants, measured at term post-menstrual age, has regional differences from that of full term infants.

Methods: 128 lead EEG data were collected during sleep from 8 ELBW infants with normal head ultrasound exams and 8 typically developing full term infants. Regional spectral power and coherence were calculated.

Cross-frequency phase coupling of brain rhythms during the orienting response.

A critical function of the brain's orienting response is to evaluate novel environmental events in order to prepare for potential behavioral action. Here, measures of synchronization (power, coherence) and nonlinear cross-frequency phase coupling (m:n phase locking measured with bicoherence and cross-bicoherence) were computed on 62-channel electroencephalographic (EEG) data during a paradigm in which unexpected, highly-deviant, novel sounds were randomly intermixed with frequent standard and infrequent target tones. Low frequency resolution analyses showed no significant changes in phase coupling for any stimulus type, though significant changes in power and synchrony did occur.

Frequency domain analyses of neonatal flash VEP.

A battery of frequency-dependent measures was made for high-density electroencephalographic recording measured in response to a flash stimulus in 12 normal term infants within 2 d of birth. Significant changes recorded in posterior electrodes in the same time window as the visual evoked potential (VEP) included increased local synchrony at approximately 40 Hz, increased power at approximately 16 Hz, the emergence of nonlinear coupling of lower (approximately 2 Hz) and higher frequency oscillations, and phase locking over a wide range of frequencies. This research provides evidence of neural synchrony and nonlinear coupling in response to a simple visual stimulus.

Electrocortical functional connectivity in infancy: response to body tilt.

To test the hypothesis that infant cortical regions activated by a head-up tilt also exhibit increased functional electrocortical connectivity, prone sleeping newborn and 2- to 4-month-old infants were tilted head-up to 30 degrees. Electroencephalogram (EEG) data were collected with 128 electrodes and coherence calculated to quantify electrocortical synchrony. Local coherence, defined as the average of coherence measurements between the EEG at each electrode site and neighboring sites (approximately 1 cm electrode spacing), was found in activated cortical regions that had previously shown increased high-frequency power with tilt.

High-density electroencephalogram monitoring in the neonate.

Early diagnosis of neurologic conditions is crucial for successful early intervention; therefore, minimally invasive diagnostic procedures are invaluable during the neonatal period. The clinical usefulness of one such technique, the electroencephalogram (EEG), is well documented. However, the advent of high-density recording systems has extended its application.

Topographic localization of electrocortical activation in newborn and two- to four-month-old infants in response to head-up tilting.

Aims: (1) To confirm that head-up tilting causes sustained increases in the heart rate (HR) of newborn infants but not during the period of maximum vulnerability to SIDS at 2-4 mo of age, and (2) to determine whether electrocortical activation (changes in high-frequency EEG power) also shows topographic and age-dependent effects of tilting.

Methods: HR and electrocortical activity were recorded in 15 newborn and 12 2- to 4-mo-old infants during head-up tilting. Infants were tilted, three times, to a 30 degrees head-up position.

Local coherence oscillations in the EEG during development in the fetal baboon.

Objective: To test the hypothesis that local coherence in extra-dural EEG recordings, a direct measure of synchronous cortical network activity, oscillates with the same periodicity as EEG power cycling and follows a similar developmental trajectory.

Methods: Local coherence was derived from continuous EEG recordings from closely spaced (1 cm) chronically implanted extra-dural electrodes over the right hemisphere in five fetal baboons (Papio sp.).

Quantitative analysis of spatial sampling error in the infant and adult electroencephalogram.

The purpose of this report was to determine the required number of electrodes to record the infant and adult electroencephalogram (EEG) with a specified amount of spatial sampling error. We first developed mathematical theory that governs the spatial sampling of EEG data distributed on a spherical approximation to the scalp. We then used a concentric sphere model of current flow in the head to simulate realistic EEG data.

Spatial correlation of the infant and adult electroencephalogram.

Objective: To examine the effects of volume conduction of current on measurements of spatial correlation in the high-density electroencephalogram (EEG) at extremes of human development: infancy and adulthood.

Methods: To calculate theoretical spatial correlation of EEG from volume conduction of uncorrelated cortical sources and compare theory with observations of intra/interhemispheric coherence.

Results: Result verified prediction of reduced spatial correlation in infants due to volume conduction.