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Many people have erratic and disturbed sleep patterns these days. Getting to bed very late at night only to watch TV or browsing the internet, waking up often during the night or simply being unable to fall asleep for very long time seem to be the typical problems of many office workers.
Physical laborers are less affected by these aliments, and you might wonder why. Well, research suggests that this can directly correlate with the use of bright computer screens until late in the evening.
Just two hours of working with an iPad at maximum brightness significantly disrupts melatonin secretion, the research found.
What is melatonin? Where it is produced in the brain? How does it work?
Melatonin is a simple organic compound which plays an important role in the body. It is produced by the pineal gland located in the center of the brain. Melatonin production is inhibited by light and stimulated by darkness. Due to this correlation, melatonin is sometimes aptly called the “darkness hormone”. Obviously, due to the location of this gland in the center of brain, light cannot reach there.
Photosensitive cells of the eye retina send the signals regarding the level of light to the pineal gland via several neuronal connections in the central nervous system and spinal cord. One of the important connecting points is the suprachiasmatic nucleus (SCN), the "master clock" of our circadian rhythm.
The circadian rhythm is the body’s sleep and wake cycle. The SCN sets the body clock, and melatonin plays the role of an adjusting or tuning mechanism. Melatonin helps to “reset” the clock, for example when we cross several time zones when traveling. Jet lag experienced by travelers is directly connected to the readjustment of circadian clocks with the help of melatonin. Melatonin synchronizes circadian cycle with the real cycle of day and night experienced by the body.
The circadian cycle can be “fooled”
Due to the connection between melatonin production and light exposure, the circadian cycle can effectively be “fooled” by provoking excessive exposure to artificial light. This is exactly what happens if we use light emitting devices like laptop computers and tablets in the evening. Exposure to light at this time of the day leads to a significant decrease in melatonin levels, sending a wake-up signal to the SCN.
Other scientific research has shown that the production of melatonin is affected not simply by light in general but by the short wave blue light (with a wavelength of approximately 470 nm). This is the bluish-white type of light generated by the screens of many of our computer devices.
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- Photo courtesy of 83905817@N08 on Flickr: www.flickr.com/photos/83905817@N08/7676645672