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How did William Harvey's research change understanding of blood circulation?

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magnetic resonance imaging — diagnosis Magnetic resonance imaging (MRI) is a powerful diagnostic technique that is used to visualize organs and structures inside the body without the need for X-rays or other radiation.

William Harvey fundamentally transformed medical understanding by demonstrating that the heart functions as a pump, circulating blood throughout the body in a closed loop.1

Before his 1628 publication, De Motu Cordis, medical thought was dominated by the Galenic view, which incorrectly posited that blood was consumed by the body and continuously produced anew by the liver. Harvey challenged this by calculating that the heart pumps more blood than the body could possibly produce or consume, necessitating a circulatory system. He further corrected the misconception that the heart’s active phase was its expansion, proving instead that the heart contracts to expel blood with force.12

Harvey’s work was a landmark in the history of medicine because it relied on the experimental method rather than traditional authority. By observing venous valves and conducting quantitative experiments, he laid the foundation for modern physiology and the study of the cardiovascular system.312