Recent research suggests that the number of exposure children has to bright light in the hour leading up to bedtime -; whether emanating from light bulbs or electronic devices -; can have a big impact on sleep-related behavior. Settling youngsters down to sleep at night isn't always easy.
There's the chemistry behind it. Our circadian rhythm -; a kind of 24-hour internal brain clock that cycles regularly between sleepiness and alertness -; employs melatonin, the body's natural sleep-inducing hormone. Melatonin is highly sensitive to light. As daylight dims toward the end of the day, our bodies are programmed to react to the reduction of light by increasing the production of melatonin. It's nature's way of ushering us toward sleep. Artificial light, however, can disrupt the circadian cycle by inhibiting the production of melatonin.