Why Do We Need to Sleep?
Sleep is a natural state of rest for members of the animal kingdom. Scientists have observed the sleep of mammals, birds, reptiles, fish, and amphibians. Although we are still not entirely sure of how sleep works, nor are we convinced that we understand all of the functions of sleep, scientists have become convinced that sleep is necessary to survival. There are a number of theories about why we sleep and what happens in our bodies and brains during sleep cycles. However, there is not currently one predominant theory. It is quite possible that there is a kernel of truth in each of these theories; that they will all work together eventually to inform a more complete understanding of human sleep. Most scientists agree that one of the major purposes of sleep is to restore and heal the body. It has been observed that hormone and immune functions change during specific stages of the sleep cycle. Furthermore, some studies have shown that sleep deprivation can lead to deficiencies in the immu
by Jeff Worley Dreamland. We spend a third of our lives in the state of relative unconsciousness, and we have no idea why,” says Bruce O’Hara, a UK associate professor of biology. “How is sleep regulated? What causes it? If it’s just a matter of physical tiredness, why can’t you just sit down, rest and be restored?” For over 20 years, these questions have intrigued O’Hara, who earned a Ph.D. in human genetics from Johns Hopkins University in 1988. His research focus there was on how human genetics affects the brain and behavior. “Something about the brain is presumably different from the rest of your body. If you sit down, your heart rate slows and muscles relax, but the brain is still just as active,” says O’Hara, who came to UK from Stanford University last August, attracted by a tenure-track position here and the promise of support to start up a lab in the Morgan Biological Sciences Building. “Sleep doesn’t make your heart rate drop much more than if you’re just sitting and relaxing
Sleep gives your brain a chance to sort things out. Scientists aren’t exactly sure what kinds of organizing your brain does while you sleep, but they think that sleep may be the time when the brain sorts and stores information, replaces chemicals, and solves problems. Skipping one night’s sleep makes a person cranky and clumsy. After missing two nights of sleep, a person will have problems thinking and doing things, his or her brain and body can’t do their normal tasks nearly as well. After five nights without sleep, a person will hallucinate. Eventually it becomes impossible for the brain to give its directions to the rest of the body without sleep. So sleep restores the body’s energy supplies that have been depleted through the day’s activities. its also the time when the body does most of its repair work like muscle tissue is rebuilt and restored. Growth hormone is secreted during sleep. This hormone is important for growth in children, but is also important throughout adulthood in
The Latest Fascinating Theories on This Mystery Phenomenon by SixWise.com With all of our advances in medicine and technology, with millions of dollars invested in numerous research studies, science still has not been able to definitively understand the purposes behind the natural, inevitable act of sleep. The exact reasons for why we do it, and why we do it for so long, remain a mystery. Most of what we do know about it comes from understanding it backward: though we don’t know why we sleep, we do know that when we don’t sleep, our health will soon suffer.
