Resting CMRO2 fluctuations show persistent network hyper-connectivity following exposure to sub-concussive collisions
Resting CMRO2 fluctuations show persistent network hyper-connectivity following exposure to sub-concussive collisions
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DOI：
10.1016/j.nicl.2019.101753
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发表时间：
2019-01-01
影响因子：
4.2
通讯作者：
Cook, Douglas J.
中科院分区：
文献类型：
--
作者：
Champagne, Allen A.;Coverdale, Nicole S.;Cook, Douglas J.
头部撞击可能会改变皮质中枢内的大脑连接，例如默认模式网络 (DMN)。然而，研究尚未考虑静息脑血流 (CBF0) 和脑血管反应性 (CVR) 改变对亚震荡冲击后连通性变化的混杂影响。在这里，使用校准的静息态 MRI 和头盔加速计对 23 名加拿大大学橄榄球运动员进行了一个赛季的追踪，以检查决定功能连接 (FC) 的神经和血管因素之间的相互作用。使用血氧水平依赖 (BOLD) 和脑耗氧代谢率 (CMRO2) 映射进行基于连通性的分析，用于纵向研究 DMN。与季前基线相比，在赛季结束后一个月观察到网络特定的 CBF0 下降，而在赛季中期和赛季结束后一个月记录了 CVR 受损。整个赛季 CBF0 和基于 BOLD 的 CVR 的变化表明，神经生理标志物在头部撞击后可能表现出不同的易感性时间线。 DMN 连接性在整个赛季中都在增加，与脑血管生理学的变化无关，这表明亚震荡影响后 FC 的变化是稳健的，并且与脑血流动力学的变化无关。本研究中没有记录撞击运动学和 DMN 连接变化之间的显着相关性。总而言之，这些发现为未来的研究创造了一个强有力的范例，以检查与反复暴露于亚震荡碰撞后网络连接性增加相关的潜在神经和血管机制，以改善接触运动中头部碰撞的管理。
Exposure to head impacts may alter brain connectivity within cortical hubs such as the default-mode network (DMN). However, studies have yet to consider the confounding effects of altered resting cerebral blood flow (CBF0) and cerebrovascular reactivity (CVR) on changes in connectivity following sub-concussive impacts. Here, 23 Canadian collegiate football players were followed during a season using calibrated resting-state MRI and helmet accelerometers to examine the interplay between the neural and vascular factors that determine functional connectivity (FC). Connectivity-based analyses using blood oxygen level dependent (BOLD) and cerebral metabolic rate of oxygen consumption (CMRO2) mapping were used to study the DMN longitudinally. Network-specific decreases in CBF0 were observed one month following the season, while impaired CVR was documented at both mid-season and one month following the season, compared to pre-season baseline. Alterations in CBF0, and BOLD-based CVR throughout the season suggest that neurophysiological markers may show different susceptibility timelines following head impacts. DMN connectivity was increased throughout the season, independent of changes in cerebrovascular physiology, suggesting that alterations in FC following sub-concussive impacts are robust and independent of changes in brain hemodynamics. No significant correlations between impact kinematics and DMN connectivity changes were documented in this study. Altogether, these findings create a strong paradigm for future studies to examine the underlying neural and vascular mechanisms associated with increases in network connectivity following repeated exposure to sub-concussive collisions, in an effort to improve management of head impacts in contact sports.