Exercise has been found to improve cognition, research has shown, although it is not known why. Aerobic exercise, such as walking or swimming, has been found to be particularly effective at making the brain think better. It is thought that exercise increases blood flow to the brain, making it easier to think more clearly, because of the additional oxygen the brain is receiving. Exercise also is thought to activate the hippocampus, an area of the brain that contributes to memory and learning. Some scientists believe that having exercise improve cognition might have developed in early humans to help them react more quickly while running for survival.
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