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Sunday, May 27, 2001
Preparing for your journey to the land of nod
By MAMI MARUKO
Apart from comfortable bedding, what kind of environment promotes deep, refreshing sleep? Many studies have been carried out to determine the answer, and although much is still not understood, it is now thought that light plays a major role in determining the quality of one's slumber.
In general, sleep is said to become shallow if bedroom lighting is brighter than 30 lux (just bright enough to be able to read a book). It is also believed that the more morning sunlight your bedroom receives, the easier -- and earlier -- you'll wake up.
Early exposure to sunlight can also help ensure healthy sleep the following night. About 14 hours after our bodies are first exposed to sunlight, the brain secretes the hormone melatonin, which causes sleepiness.
Artificial bright light is therefore used to treat those suffering from sleeping-pattern disorders such as delayed sleep phase syndrome, in which the onset of sleep occurs much later than desired.
According to Hiroyuki Suzuki, a researcher at the National Institute of Mental Health, National Center of Neurology and Psychiatry in Ichikawa, Chiba Prefecture, light therapy in the early morning may help sufferers fall asleep earlier in the evening.
The institute, which carries out physiological and psychological studies on human sleep, has a research center where those suffering from sleeping disorders are treated on an experimental basis. Sufferers stay at the institute's nearby hospital and are brought every morning to the center, where they are exposed to 5,000-lux fluorescent lamps for varying periods of time. While the optimum length of exposure is still not known, the treatment has helped a number of sufferers return to a more regular sleep pattern.
"Trying too hard to sleep is not effective. What is an optimum amount of sleep for one person might not be so for another, so you should determine the right amount for you by monitoring how easily you can do your activities during the day [in relation to the amount of sleep you had the night before]," said Suzuki.
If sleep eludes you, consider the following environmental factors as well:
Sound: If you are disturbed by background noise, try listening to the recorded sounds of birds or streams. Certain kinds of music can help soothe the mind and even prevent insomnia. Bach's "Goldberg-Variationen Aria," for example, was composed at the request of a Russian count who had difficulty sleeping and is said to be particularly soothing. To promote sleep, music should be soft and of slow tempo, and have a regular rhythm and no syncopation.
Temperature and humidity: Studies have shown that the temperature around the body in bed should be kept at around 33 C and the humidity level inside the covers at around 55 percent for the deepest sleep, while the bedroom temperature and humidity should be kept at around 25 C and 60 percent, respectively.
Smell: Aromatherapy can help induce sleep. Essential oils such as sandalwood, bergamot, lavender and Roman chamomile are recommended for relaxation. Take a lukewarm bath with a few drops of essential oil before going to bed.
Food and drink: A full or empty stomach makes it hard to achieve a sound sleep. If you are very hungry, have a small amount of an easily digestible food or drink herb tea. Caffeinated drinks such as coffee, tea, green tea, cola and hot chocolate should be consumed more than four hours before going to bed.