Sleep, a biological rhythm, is the most common altered state of consciousness. The sleep-wake cycle takes about 24 hours to complete. Spending about one-third of their time sleeping, most adults needs between seven and nine hours of sleep to function well.
When we sleep is controlled by the hypothalamus, which contains the suprachiasmatic nucleus (SCN), which influences the amount of melatonin production that is secreted. As the sun sets and daylight fades, the SCN gives a signal to the brain’s pineal gland to release melatonin. Hence, an individual starts to feel tired and hopefully falls asleep. As the night wears on and daylight fades away, the neurotransmitter serotonin also rises, which makes an individual feel tired. The SCN also controls the body’s temperature; the lower one’s body temperature is, the sleepier one feels. When the body is ready to wake up, the SCN says “stop” to the pineal gland. Melatonin decreases and the person wakes up .
Sleep is divided into four stages. Stage One is the first stage, the lightest stage of sleep. When a person is woken up here, most people do not think that they were sleeping. This is also where people sometimes experience hypnogogic images and hallucinations, this stage thought to be the reason why certain people claim to have been abducted by aliens. Theta waves dominate here. In Stage Two, called Sleep Spindles, the brain goes through brief bursts of activities. The heart rate slows down and breathing becomes shallow. Theta waves are still present here.
In Stage Three, the slower brain waves, known as Delta waves, start to roll in. When these waves hit the 50% mark, Stage Four, the deepest stage of sleep, has started. If disturbed during this stage, people are usually hard to wake up, especially kids. It is in this stage that the most growth and repair occurs.
There are two types of sleep, REM versus Non-REM. Adults spend about 20% of time in REM sleep, while infants spend 50% of time in REM. Most dreams occurs in REM sleep, a type of sleep where the muscles cannot move. In Non-REM sleep, the body can move, Non-REM helping one to achieve a more restful sleep .
Our everyday life affects sleep in a positive way. There are many factors that can improve the chance of one getting a good night’s sleep. For instance, there have been beds with special mattresses created to reduce the amount of movement one feels if their partner moves around at night. Also, there are eye patches that one can wear to reduce the light that comes into one’s bedroom, as well as shades that can be installed to keep a bedroom dark and more conducive to sleep. Trying to sleep in a room that is too hot does not work. Lowering the temperature in a room can help a person sleep, as well as putting fans in or opening a window to get some cooler air. Exercising moderately three times a week also helps one sleep. People who snore and have a condition called sleep apnea have been given a C-PAP machine, which keeps one’s breathing regular by pumping oxygen into one’s system, so a person can sleep better. Reducing one’s caffeine intake and not drinking it too close before bed can also help an individual get a better night’s sleep.
There are some teas on the market designed to help promote sleep, such as bedtime teas, stress relief teas, and tension tamer teas. Melatonin is also used by some people to increase sleep quality. We also have sleep clinics where people spend an overnight in a lab and get observed by doctors to figure out if there are any disorders affecting one’s sleep.
As we get older, our need for sleep gradually decreases. Unlike infants and teenagers who require a lot of sleep, adult bodies and brains are not growing as much. After age 65, we sleep for shorter periods of time, but still need about seven to eight hours of sleep total during the day . Eventually, our bodies only need about six hours of sleep per night. Donald Trump claims to only need about four hours of sleep per night. Some things that can get in the way of getting a full night sleep for older adults include issues with chronic pain and/or frequent urination or medications that one may be taking for other medical issues.
Our culture has changed in the way it regards sleep. On the positive side, we are plugged into ways to reduce anxiety that can help with sleep, such as doing yoga, meditation, and chanting. On the flip side, we are a more active and stressed society, many Americans working longer hours and sometimes two jobs. Many people rely on alcohol and sleeping pills to fall asleep, which reduces the amount of REM sleep one gets, which can lead to REM rebound. In REM rebound, an individual’s body catches up on REM sleep if it deprived of REM sleep for a couple nights in a row . However, this REM Rebound can make one feel sleepier during the day. People are also addicted to caffeine, thinking that the lack of sleep can be easily fixed with an Expresso or large coffee. Continuing with this cycle can be unhealthy.
Most adults needs between seven to eight hours of sleep per night. While factors such as too much caffeine and alcohol can negatively impact one’s sleep, society has also realized the benefits that exercise, mediation, and yoga can have on our sleep quality. Regulated by the brain’s hypothalamus, pineal gland, and SCN, sleep is a circadian rhythm needed for healthy functioning and cell growth and repair. The better we sleep, the greater our quality of life.
- Ciccarelli, S. K., & White, N. (2011). Psychology. New York: Pearson.
- WebMd. (2014). Sleep Well for Health. Retrieved from WebMd: http://www.webmd.com/sleep-disorders/sleep-health-10/default.htm