Bolt Taylor, Wang Shiyu, Nomi Jason S, Setton Roni, Gold Benjamin P, Frederick Blaise deB, Yeo B T Thomas, Chen J Jean, Picchioni Dante, Spreng R Nathan, Keilholz Shella D, Uddin Lucina Q, Chang Catie
Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA, USA.
Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA.
bioRxiv. 2024 Jul 29:2023.01.19.524818. doi: 10.1101/2023.01.19.524818.
The brain is closely attuned to visceral signals from the body's internal environment, as evidenced by the numerous associations between neural, hemodynamic, and peripheral physiological signals. We show that these brain-body co-fluctuations can be captured by a single spatiotemporal pattern. Across several independent samples, as well as single-echo and multi-echo fMRI data acquisition sequences, we identify widespread co-fluctuations in the low-frequency range (0.01 - 0.1 Hz) between resting-state global fMRI signals, neural activity, and a host of autonomic signals spanning cardiovascular, pulmonary, exocrine and smooth muscle systems. The same brain-body co-fluctuations observed at rest are elicited by arousal induced by cued deep breathing and intermittent sensory stimuli, as well as spontaneous phasic EEG events during sleep. Further, we show that the spatial structure of global fMRI signals is maintained under experimental suppression of end-tidal carbon dioxide (PETCO2) variations, suggesting that respiratory-driven fluctuations in arterial CO2 accompanying arousal cannot explain the origin of these signals in the brain. These findings establish the global fMRI signal as a significant component of the arousal response governed by the autonomic nervous system.
大脑与来自身体内部环境的内脏信号密切协调，神经、血液动力学和外周生理信号之间的大量关联就证明了这一点。我们表明，这些脑体共同波动可以通过单一的时空模式来捕捉。在几个独立样本以及单回波和多回波功能磁共振成像（fMRI）数据采集序列中，我们识别出静息态全脑fMRI信号、神经活动与一系列自主信号（涵盖心血管、肺、外分泌和平滑肌系统）之间在低频范围（0.01 - 0.1赫兹）存在广泛的共同波动。在静息状态下观察到的相同脑体共同波动，可由提示性深呼吸和间歇性感觉刺激引起的唤醒以及睡眠期间的自发性相位脑电图事件引发。此外，我们表明，在实验性抑制呼气末二氧化碳（PETCO2）变化的情况下，全脑fMRI信号的空间结构得以维持，这表明唤醒时伴随的动脉二氧化碳呼吸驱动波动无法解释这些大脑信号的起源。这些发现确立了全脑fMRI信号是自主神经系统控制的唤醒反应的一个重要组成部分。
