Bright light therapy resets internal clock > You might not believe it if you suffer from insomnia, but your body has an internal clock that tells it when it is time to sleep and when it is time to wake. If this clock is faulty you are suffering from what is known as a circadian rhythm sleep disorder, where your natural sleep time overlaps with regular awake activities, such as work or school (circadian means to occur in a cycle of about 24 hours). These rhythms include body temperature, alertness and the daily cycle of many hormones.
As a factor that sets your internal clock is your exposure to sunlight, light therapy is one method used to treat people with CRSD. The objective is to combine a healthy sleep pattern with your internal clock that is set at the right time, thus allowing you to enjoy the benefits of a good night’s sleep. It is claimed that exposing an insomniac to a special lamp for up to an hour can re-set the clock that is off. But does it work?
The first challenge is establishing that your inability to sleep is due to CRSD rather than a myriad of other possibilities, ranging from worry and stress, to medication and alcohol. Even if the link is established, the therapy at best it can only be regarded as part of a treatment plan.
The recommended phototherapy system consists of a set of fluorescent bulbs installed in a box with a diffusing screen, and set up on a table at which you can sit comfortably. Treatment then consists simply of sitting close to the light box, with lights on and eyes wide open. However, looking directly at the lights is not recommended. Instead you are encouraged to engage in reading, writing, or even eating. What is important is to orient the head and body toward the lights, concentrating on activities on the surfaces illuminated by the lights, and not on the lights themselves. Treatment sessions can last from 15 minutes to three hours, once or twice a day.
So are there any risks? This technology was originally developed as a cure for winter depression, which has become known as S.A.D (Seasonal Affective Disorder). Advocates of this therapy claim blood levels of the light-sensitive hormone melatonin, which may be abnormally high at certain times of day, are rapidly reduced by light exposure. However, there is no proof.
What is known is that light therapy for S.A.D can cause headaches, eyestrain or nausea. The most significant side effect is a switch to an overactive state, during which one may have difficulty sleeping, become restless or irritable, and feel over-active – hardly the desired effect! Of course, there is an alternative ….
Footnote > If you are an insomniac pensioner, the scholarly papers on this Link will make interesting reading; likewise there are many studies on the effectiveness of using light therapy to treat depression.