van de Pol Laura Anna, van 't Westende Charlotte, Zonnenberg Inge, Koedam Esther, van Rossum Ineke, de Haan Willem, Steenweg Marjan, van Straaten Elisabeth Catharina, Stam Cornelis Jan
Department of Child Neurology, VU University Medical Center, Amsterdam, Netherlands.
Department of Neonatology, VU University Medical Center, Amsterdam, Netherlands.
Front Hum Neurosci. 2018 Jul 17;12:286. doi: 10.3389/fnhum.2018.00286. eCollection 2018.
Fetal and neonatal brain connectivity development is highly complex. Studies have shown that functional networks change dramatically during development. The purpose of the current study was to determine how the mean phase lag index (mPLI), a measure of functional connectivity (FC), assessed with electroencephalography (EEG), changes with postmenstrual age (PMA) during the early stages of brain development after birth. Neonates ( = 131) with PMA 27.6-45.3 weeks who underwent an EEG for a medical reason were retrospectively studied. For each recording, global FC was assessed by obtaining a whole-head average of all local PLI values (pairwise between sensor space EEG signals). Global FC results were consequently correlated with PMA values in seven frequency bands. Local results were obtained for the frequency band with the strongest global association. There was a strong negative correlation between mPLI and PMA in most frequency bands. The strongest association was found in the delta frequency band ( = -0.616, < 0.001) which was therefore topographically explored; the strongest correlations were between pairs of electrodes with at least one electrode covering the central sulcus. Even in this heterogeneous group of neonates, global FC strongly reflects PMA. The decrease in PLI may reflect the process of segregation of specific brain regions with increasing PMA. This was mainly found in the central brain regions, in parallel with myelination of these areas during early development. In the future, there may be a role for PLI in detecting atypical FC maturation. Moreover, PLI could be used to develop biomarkers for brain maturation and expose segregation processes in the neonatal brain.
胎儿和新生儿脑连接性发育高度复杂。研究表明，功能网络在发育过程中会发生显著变化。本研究的目的是确定在出生后脑发育早期，通过脑电图（EEG）评估的功能连接性（FC）指标——平均相位滞后指数（mPLI）如何随孕龄（PMA）变化。对因医学原因接受EEG检查的131例孕龄为27.6 - 45.3周的新生儿进行回顾性研究。对于每次记录，通过获取所有局部相位滞后指数（PLI）值（传感器空间EEG信号之间的两两值）的全脑平均值来评估全局FC。随后将全局FC结果与七个频段的PMA值进行相关性分析。针对全局关联最强的频段获取局部结果。在大多数频段中，mPLI与PMA之间存在强烈的负相关。在δ频段发现了最强的关联（r = -0.616，P < 0.001），因此对其进行了地形学探究；最强的相关性存在于至少有一个电极覆盖中央沟的电极对之间。即使在这群异质性的新生儿中，全局FC也强烈反映了PMA。PLI的降低可能反映了随着PMA增加特定脑区的分离过程。这主要在脑中央区域发现，与这些区域在早期发育过程中的髓鞘形成并行。未来，PLI在检测非典型FC成熟方面可能会发挥作用。此外，PLI可用于开发脑成熟的生物标志物，并揭示新生儿脑内的分离过程。
