red blood cells (IMAGE) Penn State Caption The researchers found that red blood cell "traffic" (top grey bar) appears to contribute to oxygenation fluctuations (white line), which are not correlated to changes in neural activity (bottom blue peaks) in mice brains (top right). Credit Drew Lab and Yongsoo Kim Lab Usage Restrictions non commercial use only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.