Sleep is a normal, periodic state of body and mind, characterized by suppressed awareness, decreased sleep, relatively reduced sensory activities, decreased muscle activity and social inhibition during REM (Rapid Eye Movement) sleep, and little or no interactions with external stimuli during non REM sleep. It is a time when most of our nervous system’s processes are consolidated and stored away from further influences. A well-organized sleeping pattern ensures a good night’s sleep.
There are four stages in sleep: non REM sleep (stage I), stage 2, stage 3 and stage 4. In non REM sleep, the brain is inactive and the body is mostly inactive. Most people think that stage I and stage II sleep are the same thing, but they are actually two different stages. In the former, the brain is fully inactive, while in the latter, it is in a REM sleep.
Sleep also involves many processes such as the transmission of nerve cells from one area of the brain to another, the release of neurotransmitters like serotonin and dopamine, and the processing of information in the long term memory. The brain can only store and remember data for eight hours, thus, most memory processes happen during the REM or non REM sleep. Furthermore, REM sleep helps strengthen the connections among nerve cells. Thus, not enough sleep can cause poor long-term memory.
On the other hand, the REM sleep is where the body and mind go back to sleep. During REM sleep the brain activity increases again, the muscles at the back of the throat relax more, eyes opened and so on. The process of falling asleep once again cannot occur unless the person is fairly alert. Thus, if you are sleeping and wake up five times in the night, the chances of your waking up five times the next day are pretty high.
Besides, sleep-deprivation makes one irritable and impatient, causes drowsiness, reduced attention span and can affect moods. Chronic sleep-deprivation can cause depression and anxiety as well. A study conducted by the National Institute of Mental Health found that sleep-deprivation has an impact on the cognitive performance of those individuals suffering from depression. In addition, chronic insomnia has a negative impact on the body’s immune system. Sleep-deprivation can also lead to poor memory and increased susceptibility to diseases such as Alzheimer’s.
Other studies have indicated that sleep deprivation can lead to serious medical conditions like diabetes, hypertension, heart disease and psychiatric disorders. It has also been discovered that sleep deprivation has a negative impact on the immune system of the body. The various implications of sleep deprivation can be reduced sexual drive in men, increased blood pressure in women, lower mental capability in children, lower IQ in adults, higher chances of accidents at work, lower work efficiency and so on. Therefore, it can be concluded that the sleep you get may be important for your overall health.