Question

What are the roles, meanings, cycles, and disorders of sleep in human functioning?

Answer 1

Sleep is a naturally occuring state of mind and body that is characterized by altered consciousness, relatively inhibited sensory activity and inhibition of nearly all voluntary muscles. Sleep is vital for the overall health and functioning of the body processes. It is necessary for healthy brain function as well as emotional well being. The brain forms new pathways as one minutes, and in elp one learn and remember information. In case of physical health, sleep is involved in repairing and healaing of the heart and blood vessels. Sleep deficincy over a long period of time is linked to an increase in the risk for heart diseases, high blood pressure, diabetes and strokes. It also helps in maintaining a healthy balance of the hormones, as well as the body's reaction to insulin which controls the blood sugar level.

Each sleep cycle lasts for around 90 minutes, and in each cycle, we go through 5 stages. The first 4 stages make up for NREM(Non rapid eye movement) and the last one is when REM(Rapid eye movement) occurs. During NREM, sleep varies from very light to deep sleep in stage4, and it is generally very difficult to wake someone up in this stage. In the final stage, the REM, is when most of the dreaming occurs, as the eyes move back and forth, it is believed that the eye movements correspond to visual images, however it is not confirmed. During this stage, the muscles in our bodies are paralyzed although the heart and the diaphragm continue to function noramlly.

Some of the most common sleep disorders faced by people are:

Insomnia which is when people have difficulty in falling asleep orr staying asleep. They often wake up in the middle of the night and find it difficult to go back to sleep. Some also have the problem of feeling unrefreshed even though they may have slept through the night. It is associated with chronic fatigue, loss of appetite, problems with the mood and concentration are also results of not sleeping well.

Another common sleep disorder is sleep apnea which s a potentially serious sleep disorder that occurs when a person's breathing is interrupted during sleep. People with untreated sleep apnea stop breathing repeatedly during their sleep. There are two types of sleep apnea: obstructive and central. Obstructive sleep apnea (OSA) is the more common of the two. It is caused by a blockage of the airway, usually when the soft tissue in the back of the throat collapses during sleep. In central sleep apnea (CSA), the airway is not blocked but the brain fails to tell the body to breathe. This type is called central apnea because it is related to the function of the central nervous system. Symptoms of OSA may include snoring, daytime sleepiness, fatigue, restlessness during sleep, gasping for air while sleeping and trouble concentrating. Those with CSA may have gasping for air but mostly report recurrent awakenings during night.