If a particular part of the brain is working more than another part, this causes a change in the amount of oxygenated blood flowing to that part of the brain. (caltech.edu)
Clarity of the body and mind comes from increased oxygenated blood flowing through you. (mindbodygreen.com)
TG > your heart is a muscle / organ which pumps oxygenated blood around your body.. (religion.blogs.cnn.com)