Chen Donna Y, Di Xin, Yu Xin, Biswal Bharat B
Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA.
Rutgers Biomedical and Health Sciences, Rutgers School of Graduate Studies, Newark, NJ, USA.
bioRxiv. 2023 Aug 21:2023.08.18.553848. doi: 10.1101/2023.08.18.553848.
Functional MRI (fMRI) measures the blood-oxygen-level dependent (BOLD) signals, which provide an indirect measure of neural activity mediated by neurovascular responses. Cerebrovascular reactivity affects both task-induced and resting-state BOLD activity and may confound inter-individual effects observed in BOLD-based measures, such as those related to aging and biological sex. To investigate this, we examined a large open-access fMRI dataset containing a breath-holding task, checkerboard task, and resting-state scans. We used the breath-holding task to measure cerebrovascular reactivity, used the checkerboard task to obtain task-based activations, and from the resting-state data, we quantified the resting-state amplitude of low-frequency fluctuations (ALFF), and resting-state regional homogeneity (ReHo). We hypothesized that cerebrovascular reactivity would be correlated with BOLD measures and that accounting for these correlations would result in better estimates of age and sex effects. Our analysis showed that cerebrovascular reactivity was correlated with checkerboard task activations in the visual cortex and with ALFF and ReHo in widespread fronto-parietal regions, as well as regions with large vessels. We also found significant age and sex effects in cerebrovascular reactivity, some of which overlapped with those observed in ALFF and ReHo scores. Finally, we demonstrated that correcting for the effects of cerebrovascular reactivity had very limited influence on the estimates of age and sex. Our results highlight the limitations of accounting for cerebrovascular reactivity with the current breath-holding task.
功能磁共振成像（fMRI）测量血氧水平依赖（BOLD）信号，该信号提供了由神经血管反应介导的神经活动的间接测量。脑血管反应性会影响任务诱发的和静息状态下的BOLD活动，并且可能混淆在基于BOLD的测量中观察到的个体间效应，例如与衰老和生物性别相关的效应。为了对此进行研究，我们检查了一个大型开放获取的fMRI数据集，其中包含屏气任务、棋盘格任务和静息状态扫描。我们使用屏气任务来测量脑血管反应性，使用棋盘格任务来获得基于任务的激活，并且从静息状态数据中，我们量化了低频波动的静息状态幅度（ALFF）和静息状态区域同质性（ReHo）。我们假设脑血管反应性将与BOLD测量相关，并且考虑这些相关性将导致对年龄和性别效应的更好估计。我们的分析表明，脑血管反应性与视觉皮层中的棋盘格任务激活以及广泛的额顶叶区域以及大血管区域中的ALFF和ReHo相关。我们还在脑血管反应性中发现了显著的年龄和性别效应，其中一些与在ALFF和ReHo分数中观察到的效应重叠。最后，我们证明校正脑血管反应性的影响对年龄和性别的估计影响非常有限。我们的结果突出了用当前屏气任务考虑脑血管反应性的局限性。
