Sleep Did you know that today 75 percent of us dream in color and before color television, only 15 percent of us did? Or that you’ll sleep better during a new moon and worse during a full moon? Or that it’s not uncommon for deaf people to sign in their sleep? Those are just a few weird things about sleep that most people don’t know. Sleep is a necessity because you need sleep to function properly throughout your day.Why We Sleep Scientists have investigated why we sleep from a lot of different angles. They have had many studies, but, despite all their work, the question has been difficult to answer. There are many theories as to why we sleep such as the Inactive Theory and the Energy Conservation Theory. The Inactivity Theory states that inactivity at night is an adaptation that has served as a survival function. The Energy Conservation Theory states that sleep is used to lower an individual’s energy call and waste during the day or night, especially at times when it is least active to search for food. No one knows if one single theory will ever be proven correct.How Much Sleep Do We Need Some people believe that you need 8 hours of sleep, others believe that depending on your age the time is different. Most people believe that infants need 12 to 15 hours of sleep, toddlers need 11 to 14 hours, and preschoolers need 10 to 13 hours of sleep. School age kids need 9 to 11 hours of sleep, teenagers need 8 to 10 hours, young adults need 7 to 9 hours, adults need 7 to 9 hours, and older adults need 7 to 8 hours of sleep. Everyone needs healthy sleep because we all need to store information and learn skills to succeed in life. This is likely part of the reason children need more sleep than adults.Types and Stages of Sleep There are many types and stages of sleep. The different types and stages can be recognized using polysomnography, that measures many body functions such as brain wave activity, eye movement, respiration, muscle activity, heart rhythm etc. There are two main types of sleep, rapid eye movement and non-rapid eye movement. Each type can be divided into three or four separate stages. Non-rapid sleep is occasionally referred to as “quiet sleep” and rapid as “active sleep”, but these are not scientific terms.Non-rapid sleep is distinguished by slow but logically high amplitude or high voltage oscillations rapid sleep shows a faster and lower amplitude trace, more similar to normal waking activity. Brain waves during non-rapid sleep tend to be greatly synchronized, and those during rapid sleep more unsynchronized. Electromyogram traces of skeletal muscle activity shows that, when the body is paralyzed during rapid sleep, the body does make some small movements during non-rapid sleep, containing a major change in body position around once every twenty to thirty minutes. Benefits Enough sleep is a crucial part of a healthy life. Seep can benefit your weight, heart, mind, and more. Your mind is surprisingly busy while you sleep. During sleep you can boost your memories and “practice” skills you learned while you were awake. If you are trying to learn something new, you will work better after sleeping. Sleeping also affects the quality of life. In a study of women ages 50 to 75, more deaths occured in women who got less than 5 minutes or more than 6 and a half hours of sleep per night. Sleeping helps you function properly during your day. Scientists have examined why we sleep from many different angles. No one actually knows why we sleep, but there are many different theories. On average, we need 8 hours of sleep. There are two types of sleep, rapid eye movement non-rapid eye movement. Each type can be divided into three or four different stages. You will perform better after sleeping. Sleeping benefits many things such as your heart, weight, mind, and more.