Sleep is the natural, ongoing state of body and mind, often characterized by decreased perception, fairly restricted sensory activity, decreased motor activity, decreased muscle activity and synchronization of almost all voluntary muscles during REM sleep, and decreased interactions with environment during waking hours. The amount of sleep required to fully recuperate for the following day’s activities usually varies from person to person, from five to twelve hours. There are also those who do not need to sleep at all during the day. But for individuals who have trouble sleeping, or whose sleeping patterns are constantly interrupted by stress, worry, anxiety, fatigue, depression, mental challenges, or other factors, getting enough sleep is important to maintain normal health. Some of the potential causes of insufficient sleep are insomnia, too much sleep, excessive day sleepiness, poor diet, and other underlying disorders.
To help determine a person’s individual sleep needs, there are several physical and physiological markers that can be used. These include the duration of stage 1 sleep ( REM sleep ), the timing of the light and deep stages of sleep, the muscle activity level and sensitivity to light and sound, the sleep quality, and the sleep homeostasis, or ability of the body to maintain a state of wakefulness over a period of time. If one has undergone testing to measure levels of certain brain chemicals, such as dopamine, melatonin, serotonin, and GABA, it can also be an indicator of a good night’s sleep. Some patients who suffer from sleep apnea sometimes fail to respond to treatments, even if they are tested for a lack of sleep.
There are many causes of sleep problems. One of the most common sleep disturbances is physical health or medical conditions, such as sleep apnea, restless leg syndrome, sleepwalking, and other motor vehicle accidents. According to the national sleep foundation, almost one in ten adults have some form of sleep disorder, such as insomnia, sleepwalking, sleep apnea, or a sleeping disorder related to breathing problems. One in seven adults have serious health problems related to sleep, such as obesity, depression, diabetes, heart disease, or other cardiovascular problems.
Serious sleep deprivation can lead to physiological issues such as irritability, memory loss, increased blood pressure and cholesterol levels, decreased sex drive, and increased risk of death from diseases such as Alzheimer’s disease, cancer, and stroke. Other sleep problems, which are less serious and frequently experienced by most people, such as jet lag, anxiety and stress, restless sleep, snoring, sleep paralysis, or sleepwalking, may be indicators of more serious underlying conditions. In these cases, getting enough sleep may be as important as undergoing treatment for the sleep disorder.
Studies have shown that bright lights or loud noises can seriously impact sleep patterns. Studies have found that sleep can become severely disrupted when exposed to extremely loud sounds or light. In a sleep study conducted by the American Society for Testing and Materials, sleepers were exposed to four different types of noise: 100 decibel; sound with a frequency of one million hertz; over 500 decibel; and extremely quiet. Those who listened to the very loud noise were more likely to have trouble falling asleep or staying asleep than those who slept in a quieter room. Over sixty percent of people surveyed admitted they often listen to music at night or watch television while they are sleeping.
Rapid eye movement sleep (RIMS) is divided into three stages, each of which is characterized by different sleep symptoms. Stage 1 sleep is the longest stage of sleep; Stage 2 is characterized by slow, restorative sleep; and Stage 3 is the deepest sleep. RIMS sufferers often report having trouble getting back to Stage 1 or Stage 2 sleep if their room is too bright or there is too much noise.