Lopera-Perez Diana C, Nayak Srishti, Stangier Giulia, Tuladhar Charu T, St John Ashley M, Grieve Philip G, Tarullo Amanda R
Department of Psychological and Brain Sciences, Boston University, Boston, Massachusetts, USA.
Department of Otolaryngology-Head & Neck Surgery, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Dev Psychobiol. 2022 Feb;64(4):e22265. doi: 10.1002/dev.22265.
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. In contrast, there were no differences between social and nonsocial conditions for infants from economically strained families or infants whose mothers used lower proportions of infant-directed speech. This study demonstrates that neural organization differs between a nonsocial baseline and a social interaction, but said differentiation is not present for infants from less privileged backgrounds. Our results underscore the importance of examining brain activity during species-typical contexts to understand the role of environmental factors in brain development.
社交互动对婴儿大脑发育至关重要，但我们对婴儿在社交和非社交情境下的功能连接如何不同，或者对情境差异的敏感度如何与早期的远端和近端环境因素相关知之甚少。我们比较了12个月大婴儿在社交和非社交条件下的半球内脑电图（EEG）连贯性，然后研究了条件之间的差异是否随家庭经济压力以及6个月时的两种母亲行为（积极情绪和面向婴儿的言语）而变化。我们发现，在社交条件下，从额叶区域到中央、顶叶、颞叶和枕叶区域的EEG连贯性较低，但仅适用于高收入家庭的婴儿以及其母亲使用较高比例面向婴儿言语的婴儿。相比之下，经济紧张家庭的婴儿或其母亲使用较低比例面向婴儿言语的婴儿在社交和非社交条件之间没有差异。这项研究表明，非社交基线和社交互动之间的神经组织存在差异，但这种差异在背景较差的婴儿中不存在。我们的结果强调了在物种典型情境中检查大脑活动对于理解环境因素在大脑发育中的作用的重要性。
