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bioRxiv · 10.1101/2020.09.18.303164

Origins of 1/f-like tissue oxygenation fluctuations in the murine cortex

Zhang, Q.·Gheres, K. W.·Drew, P. J.
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Abstract

The concentration of oxygen in the brain spontaneously fluctuates, and the power distribution in these fluctuations has 1/f-like dynamics. Though these oscillations have been interpreted as being driven by neural activity, the origins 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 ( stalls) and mathematical modelling show that stochastic fluctuations in erythrocyte flow and stalling could underlie 1/f-like dynamics in oxygenation. These results show discrete nature of erythrocytes and their irregular flow, rather than neural activity, could drive 1/f-like fluctuations in tissue oxygenation.

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Zhang, Q., Gheres, K. W., Drew, P. J.. 2020-09-20. Origins of 1/f-like tissue oxygenation fluctuations in the murine cortex. https://doi.org/10.1101/2020.09.18.303164

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