However some recent research indicated that bright light applied to the back of an individual's knee could shift human circadian rhythms. This suggests that the bloodstream, not just the neurons of the visual pathways, might mediate the biological clock. How the Light Box is used Before embarking on a course of light treatment, it is best to have a complete psychiatric evaluation. Sometimes a medical illness or another psychiatric condition can masquerade as depression. Discuss various treatment alternatives with your doctor.
Light therapy does take time, and regular use.
Like exercise, not everyone who would benefit from it will actually do it on a regular basis. Your doctor will discuss the various types of light boxes or visors available. The time spent in front of the light is related to the intensity of the light source and the distance one sits from the light. I will often lend out a box for a month so that the individual can see whether it helps before purchasing a box. Some individuals who use a 10,000-lux box may only need 30 minutes of daily light treatment.