Center for Neural Engineering, Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
Graduate Program in Molecular Cellular and Integrative Biosciences, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
PLoS Biol. 2021 Jul 15;19(7):e3001298. doi: 10.1371/journal.pbio.3001298. eCollection 2021 Jul.
The concentration of oxygen in the brain spontaneously fluctuates, and the distribution of power in these fluctuations has a 1/f-like spectra, where the power present at low frequencies of the power spectrum is orders of magnitude higher than at higher frequencies. Though these oscillations have been interpreted as being driven by neural activity, the origin of these 1/f-like oscillations is not well understood. Here, to gain insight of the origin of the 1/f-like oxygen fluctuations, we investigated the dynamics of tissue oxygenation and neural activity in awake behaving mice. We found that oxygen signal recorded from the cortex of mice had 1/f-like spectra. However, band-limited power in the local field potential did not show corresponding 1/f-like fluctuations. When local neural activity was suppressed, the 1/f-like fluctuations in oxygen concentration persisted. Two-photon measurements of erythrocyte spacing fluctuations and mathematical modeling show that stochastic fluctuations in erythrocyte flow could underlie 1/f-like dynamics in oxygenation. These results suggest that the discrete nature of erythrocytes and their irregular flow, rather than fluctuations in neural activity, could drive 1/f-like fluctuations in tissue oxygenation.
大脑中的氧气浓度会自发波动，这些波动的功率分布具有 1/f 样的频谱，其中频谱低频处的功率比高频处高出几个数量级。尽管这些振荡被解释为是由神经活动驱动的，但 1/f 样振荡的起源还不是很清楚。在这里，为了深入了解 1/f 样氧波动的起源，我们研究了清醒行为小鼠的组织氧合和神经活动的动力学。我们发现，从小鼠皮层记录的氧信号具有 1/f 样频谱。然而，局部场电位中的带限功率并没有表现出相应的 1/f 样波动。当局部神经活动受到抑制时，氧浓度的 1/f 样波动仍然存在。红细胞间距波动的双光子测量和数学建模表明，红细胞流的随机波动可能是氧合 1/f 样动力学的基础。这些结果表明，红细胞的离散性及其不规则流动，而不是神经活动的波动，可能驱动组织氧合的 1/f 样波动。
Zotero 插件
