Sleep is defined as a natural and periodic resting condition of the body and mind in which eyes are closed, muscles, nervous system, etc. are relaxed, and consciousness of the world is suspended so that body movement and response to external stimuli is decreased.

During sleep the brain in humans and other mammals undergoes a characteristic cycle of brain-wave activity that includes intervals of dreaming. It generally occurs in night or day for a certain period of time. 

 

(1)Sleep benefits to our mood, memory and concentration. Sleep helps to organize memories, solidify learning, and improve concentration. Proper sleep, especially sleep where you are actively dreaming (REM sleep), regulates mood as well. Lack of sleep can make you irritable and cranky, affecting your emotions, social interaction, and decision making. Sleep deprivation also affects motor skills, enough to be similar to driving while drunk if seriously sleep deprived.

(a) Immune system. Sleep is essential to the immune system. Without adequate sleep, the immune system becomes weak, and the body becomes more vulnerable to infection and disease. 

(b) Nervous system. Sleep is also a time of rest and repair to neurons. Neurons are the freeways of the nervous system that carry out both voluntary commands, like moving your arm, and involuntary commands, like breathing and digestive processes.

(c) Hormone release. Many hormones, substances produced to trigger or regulate particular body functions, are timed to release during sleep or right before sleep. Growth hormones, for example, are released during sleep, vital to growing children but also for restorative processes like muscle repair.

(d) Brain cellular repair, replenishment and growth. Recent studies have suggested that sleep downtime of the brain, so active during the day, may replenish dwindling energy stores that cells need to function, repair cellular damage caused by our busy metabolism, and even grow new nerve cells in the brain. 

 

Sleep deprivation occurs when you are not sleeping the right amount for your individual needs. Sometimes sleep deprivation is short term, like a college student pulling an all nighter. Chronic sleep deprivation often occurs in professions who work long hours, caregivers with multiple responsibilities, a concurrent sleep disorder or another disease that interferes with sleep.

Other signs you may be suffering from sleep deprivation include:-

                                  (a) Difficulty waking up in the morning

                                  (b) Poor performance in school, on the job, or in sports

                                  (c) Increased clumsiness

                                  (d) Difficulty making decisions

                                  (e) Falling asleep during work or class

                                  (f) Feeling especially moody or irritated, etc.

Sleep deprivation can be dangerous not only to you but others, since it affects motor skills like driving. Chronic sleep deprivation is also thought to cause long term changes to the body, which contribute to increased risk for obesity, diabetes and heart disease.

Sleep requirements are highly individual and depend on many factors:

                                       -your age and genetic makeup

                                       -what you do during your waking hours, including exercise

                                       -the quality of your sleep

 

To consistently meet sleep requirements for both deep sleep and REM sleep, you need to set the stage for good sleep on a daily basis. This involves:

                                        -improving your daytime habits

                                        -creating a better sleep environment

                                        -avoiding food and drink that might interfere with sleep

                                        -developing a good bedtime routine