The third trimester is a critical period for the development of functional networks that support the lifelong neurocognitive performance, yet the emergence of neuronal coupling in these networks is poorly understood. Here, we used longitudinal high-density electroencephalographic recordings from preterm infants during the period from 33 to 45 weeks of conceptional age (CA) to characterize early spatiotemporal patterns in the development of local cortical function and the intrinsic coupling modes [ICMs; phase–phase (PPCs), amplitude–amplitude (AACs), and phase–amplitude correlations (PACs)]. Absolute local power showed a robust increase with CA across the full frequency spectrum, while local PACs showed sleep state-specific, biphasic development that peaked a few weeks before normal birth. AACs and distant PACs decreased globally at nearly all frequencies. In contrast, the PPCs showed frequency- and region-selective development, with an increase of coupling strength with CA between frontal, central, and occipital regions at low-delta and alpha frequencies together with a wider-spread decrease at other frequencies. Our findings together present the spectrally and spatially differential development of the distinct ICMs during the neonatal period and provide their developmental templates for future basic and clinical research.

妊娠晚期是支持终生神经认知表现的功能网络发展的关键时期，但人们对这些网络中神经元耦合的出现知之甚少。在这里，我们使用早产儿在 33 至 45 周孕龄 (CA) 期间的纵向高密度脑电图记录来表征局部皮质功能发育的早期时空模式和内在耦合模式 [ICMs;相位-相位（PPC）、幅度-幅度（AAC）和相位-幅度相关性（PAC）]。绝对局部功率在整个频谱范围内显示出 CA 的强劲增加，而局部 PAC 显示出睡眠状态特异性的双相发展，在正常出生前几周达到顶峰。 AAC 和遥远的 PAC 几乎在所有频率上都在全球范围内下降。相比之下，PPC表现出频率和区域选择性发展，在低δ和α频率下，额叶、中央和枕骨区域之间与CA的耦合强度增加，而在其他频率下则更广泛地降低。我们的研究结果共同呈现了新生儿时期不同ICM的光谱和空间差异发育，并为未来的基础和临床研究提供了它们的发育模板。