Sleep is an important aspect for all living creatures and is required to maintain and restore proper and healthy bodily functions. A natural sleep cycle according to the medical dictionary is defined as a normal daily twenty four hour routine that includes both sleep and wake times. The human body is controlled by two interacting and interdependent systems which determine wakefulness and sleep. They are the internal biological clock and the sleep-wake homeostat and under normal healthy circumstances, help us stay awake during daylight and help us sleep at night. A normal healthy human being should get at least 7 to 8 hours of uninterrupted sleep every 24 hours.
Types of natural sleep
Technological and scientific research and advancement reveals that the brain never shuts down or gets turned off in a living organism during natural sleep. By using sophisticated equipment to study sleep patterns called an electroencephalograms (EEGs), scientists have been able to measure brain activities and discovered two types of natural sleep, (REM) rapid-eye-movement sleep and (NREM) non-rapid-eye-movement sleep.
REM sleep is aptly named as it is characterized by small, quick and fast rhythms and eye movement which are visible even to the naked eye. Sleep scientists tended to agree that it is during this type of sleep that people dream. NREM sleep comes after REM sleep and is progressive happening in three distinct stages where brain activity as displayed in on the EEG become slower and eye movement reduces till it stops. A person at this point is deeply asleep and does not even dream.
Natural sleep cycle at night
Research shows that a normal healthy human being begins with NREM sleep when one nods off in the first stage that lasts between one and seven minutes. The second stage of NREM takes over naturally and lasts anywhere between ten to twenty five minutes. The third stage which lasts between twenty and forty minutes is characterized by deep sleep and one can barely hear anything in their surroundings. At this point brain activity is greatly reduced and an individual is not easily awakened at this stage of sleep.
REM sleep kicks in sixty to one hundred minutes after NREM sleep and will take up a quarter of a normal human beings sleep time. This is when most people experience dreams and depending on one’s frame of mind and occupation during the day, dreams will vary on intensity and length. NREM and REM sleep patterns will thereafter continue, alternating at varying intervals which explain why some people report hearing activity at movement while asleep.
A normal healthy human being should be able to naturally fall asleep and experience all the types of natural sleep patterns. However due to several external factors such as ill health, poor eating and exercise habits as well as use and abuse of drugs, some people have completely altered their natural sleep cycles resulting in irregular and even sleepless nights. The natural sleep cycle can however be restored by behavior and attitude change.