Chapter 10:Inner Rhythms

I particularly found this chapter to be one of the most interesting chapters in the book. It looks at the chaos found within the human body. First it takes a look at the heart. Even though the cardiac pattern is periodic, there are numerous nonperiodic pathologies which lead to a person’s death. When a doctor listens to a person’s heartbeat, he hears the pounding of fluid. Blood enters the heart through two large veins, the inferior and superior vena cava, emptying blood without oxyen from

 the body to the right atrium. The pulmonary veins empty oxygen-rich blood from the lungs to the left atrium. Blood flows from the right atrium into the right ventricle, and when the ventricles are full, the tricuspid valve shuts. Blood leaves the heart through the pulmonic valve, and enters the lungs through the pulmonary artery. When an artery is blocked, ventricular fibrillation occurs and a person dies. As an arrhythmia, disorders of the heart's regular rhythmic beating, occurs, the heart’s muscles beat in an ncoordinated fashion as it tries to pump blood. The heart cannot stop fibrillating on its own, it needs a jolt of electricity from a defibrillation device. This is because the chaotic motion is stable over time.

Two unsolved problems many people suffer at some point of their lives are jet lag and insomnia. People have a steady sleep-wake rhythm and body temperature cycle which can restores itself after disturbance. In isolation, without daily resetting cues, the temperature cycle is 25 hours, with low temperatures occurring at night. However, experiments by German researchers found that the sleep-wake cycle became independent of one another, as they became chaotic. The experiment subjects would stay awake for twenty hours, and then sleep for ten hours, while being totally unaware of the time if day. After returning to the real world, the time it took for the participants to return to normal varied greatly.

 

After looking at these chaotic behaviours, it is a wonder how the human body works perfectly in disorder. How does the rhythm of the heart suddenly become chaotic and uncontrolled? How do sleep pattern affect the physiology of the body? It is beyond our understanding how much stress our bodies can take before the inevitable happens.