The "flow" of red blood cells contributes to changes in brain oxygenation

Adequate blood flow provides oxygen and nutrients to the brain, but oxygenation tends to fluctuate in a unique and consistent way

Now, researchers at Pennsylvania State University have determined one reason for this fluctuation: the inherent randomness of the flow rate of red blood cells through the capillaries

Patrick Drew, Hack Distinguished Associate Professor of Engineering Science and Mechanics, Neurosurgery, and Biomedical Engineering said: "These oxygenation fluctuations also occur in other tissues, such as muscles

This kind of fluctuation is similar to 1/f noise, which is a statistical model that shows large fluctuations composed of many small fluctuations, and various phenomena such as stock market prices to river heights occur naturally

First, the researchers monitored the blood flow, oxygenation, and electrical signals generated by brain activity in awake mice—according to Drew, this was the first time that the latter two were tracked at the same time

Next, in order to study the relationship between brain activity and oxygenation fluctuations, the researchers used pharmaceutical compounds to temporarily and reversibly suppress nerve signals in the mouse brain

However, the delivery of red blood cells tells us a different story

"It's like traffic," Drew said

Importing experimental data into statistical models allows researchers to perform further simulations and make inferences based on the large amount of data generated by the model

Drew said that a better understanding of the regulation of blood flow and subsequent oxygen transport could help researchers improve medical technology and explore the causes of diseases such as Alzheimer's

Kyle Gheres of the Inter-School of Molecular Cellular and Integrated Biological Sciences graduate program also participated in this paper

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