What is bright light therapy?

By Professor Colin Espie

There is evidence that naturally occurring light regulates the human sleep-wake cycle, and that both exposure to natural light, and to artificial bright light (using a 'light-box') can have sleep phase altering properties. The greatest evidence for benefit, however, is with Circadian Rhythm Sleep Disorders, rather than with poor sleep. There are a few studies, indicating that bright light can be used along with CBT as part of a treatment program for poor sleep, but this is applies only when someone has a severe difficulty with getting to sleep every night, or wakes up very early every morning.