Somatosensory-evoked delta brush activity in very pre-term infants
Somatosensory-evoked delta brush activity in very pre-term infants
复制标题
极早产儿体感诱发的 Delta 刷活动
DOI：
--
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
L. Fabrizi
中科院分区：
文献类型：
--
作者：
K. Whitehead;Pureza Laudiano;R. Pressler;J. Meek;L. Fabrizi
简介：
Delta 刷——具有压倒性的 α-β 振荡的慢波——是早产儿脑电图的一个标志，可以通过体感刺激诱发（Whitehead 等，2017）。因此，它们可能是早期感觉处理的生物标志物，其衰减表明体感回路的成熟。在动物模型中，已知体感系统在头尾进展中成熟，后肢体感最后发育，但对人类婴儿大脑中体感处理的发展知之甚少。在这里，我们研究了早产期手脚触觉刺激后三角洲刷活动的衰减。
方法：
我们记录了 16 通道脑电图，并评估了 38 名神经发育不良风险较低的早产儿（排除：（i）脑室内出血⩾ III 级；（ii）严重生长受限（定义为<第二出生体重百分位数））手脚触觉机械刺激后的体感诱发反应。然后，我们使用逐点 t 检验（统计显着性设置为 p<0.01，以考虑多个早产儿（28+2−31+2 周+天，n=13）和中度早产儿（32+2−35+4 周+天，n=25）之间的慢 δ 波振幅和诱发反应中压倒性的 α-β 振荡的变化。比较）。
结果：
手和脚的触觉刺激引起持久的弥漫性负δ慢波，起始潜伏期为~100ms，峰值潜伏期为~500ms，手部和足部刺激的峰值幅度分别为~100μV和~50μV，并且与该慢波的峰值潜伏期同时出现的α-β振荡增加。
我们首先观察慢δ波振幅的变化。在老年组中，这种δ波的幅度衰减在手部刺激的对侧顶叶区域最为显着，并且在足部刺激的中线顶叶和双侧颞区最为显着。接下来，我们观察了与慢 Delta 波的峰值潜伏期同时发生的 α-β 振荡幅度的变化。在手部刺激的双侧顶叶区域，老年组的α-β振荡幅度减弱，而足部刺激的年龄组之间没有差异。
结论：
这是对上肢和下肢刺激引起的三角刷的首次发育研究。我们的研究结果表明，在极早产儿中，触觉刺激会引起弥漫性三角洲刷活动，这种活动在顶颞区的发育过程中衰减最为明显。有趣的是，Delta 刷 α-β 振荡仅随着手部刺激的发育而减少，而不是足部刺激，这表明手部的体感成熟可能会更早，这与对较大婴儿的研究（Whitehead 等人，已提交出版）和动物模型的研究一致。
INTRODUCTION:
Delta brushes - slow waves with over-riding alpha-beta oscillations - are a hallmark of the pre-term EEG, and can be evoked by somatosensory stimulation (Whitehead et al., 2017). As such, they may be a biomarker of early sensory processing, with their attenuation indicating maturation of somatosensory circuits. In animal models, the somatosensory system is known to mature in a rostro-caudal progression, with hindlimb somatosensation last to develop, but little is known about the development of somatosensory processing in the human infant brain. Here we investigated the attenuation of delta brush activity following tactile stimulation of hands and feet over the pre-term period.
METHODS:
We recorded 16-channels EEG and evaluated the somatosensory evoked response following tactile mechanical stimulation of hands and feet in 38 pre-term infants at low-risk of adverse neurodevelopment (exclusion: (i) intra-ventricular haemorrhage ⩾ grade III; (ii) severe growth restriction (defined as <2nd birth weight centile)). We then looked at changes in the amplitude of the slow delta wave and of the over-riding alpha-beta oscillations in the evoked response between very pre-term (28 + 2 − 31 + 2 weeks + days, n = 13) and moderately pre-term (32 + 2 − 35 + 4 weeks + days, n = 25) infants using point-by-point t-tests (statistical significance set at p < 0.01 to account for multiple comparisons).
RESULTS:
Tactile stimulation of hands and feet evoked a long-lasting diffuse negative delta slow wave, with onset latency at ∼100 ms, peak latency at ∼500 ms, and peak amplitude of ∼100 μV and ∼50 μV for hand and foot stimulation respectively, and an increase in alpha-beta oscillations concurrent with the peak latency of this slow wave.
We first looked at changes in the amplitude of the slow delta wave. This delta wave attenuated in amplitude in the older age group most prominently over the contralateral parietal-temporal region for hand stimulation, and most prominently over the midline parietal and bilateral temporal regions for foot stimulation. Next, we looked at changes in the amplitude of the alpha-beta oscillations which co-occurred with the peak latency of this slow delta wave. Alpha-beta oscillations attenuated in amplitude in the older age group over bilateral parietal regions for hand stimulation, while there was no difference between the age groups for foot stimulation.
CONCLUSION:
This is the first developmental study of delta brushes evoked by stimulation of the upper and lower limbs. Our results indicate that in very pre-term infants tactile stimulation evokes diffuse delta brush activity, which attenuates across development most markedly over the parietal-temporal regions. Interestingly, delta brush alpha-beta oscillations only decrease with development for hand stimulation, but not foot stimulation, suggesting that somatosensory maturation may occur earlier for the hands in line with studies of older infants (Whitehead et al., submitted for publication), and animal models.