Can't Sleep? This May Be the Simple Reason Why (and It's Easy to Fix)
Our modern lifestyles may no longer be constrained by sunrise and sunset, but light remains one of the most powerful influences on our behavior and wellbeing. This realization has fuelled a “sleep hygiene” movement, whose proponents point out that bright lights before bedtime and spending the whole day in a dimly lit office can dampen the natural circadian cycle, leaving people in a continual mental twilight – dozy in the morning, and too alert to fall asleep promptly at night