|
|
 |
Natural light is an essential part of daily life. Light regulates our "biological clock" - a small cluster of cells in the brain that governs our sense of time and affects how energetic and alert we feel. The positive effect of bright artificial light on human mood and performance has been thoroughly researched and is recognized by many respected organizations, including the National Institute of Health, the American Psychiatry Association, and the U.S. Department of Health and Human Services.
Most people feel active and upbeat when they get lots of natural light during the sunny days of spring and summer. But the short, dark days of winter can have the opposite effect. |
When natural light is limited, many people gain weight, have trouble getting out of bed in the morning, and generally feel lethargic and moody - all symptoms of what is commonly known as "winter blues". Most people who experience winter blues can get prompt relief by using BioBrite's healthy lighting products.
The timing of light signals can be as important as how much light we receive. When the biological clock receives light signals at the wrong time of day, it can become out of sync with the real world, creating havoc with sleep patterns, digestion, and other activities. This phenomenon, called "circadian dysrthmia," is most often experienced in the form of "jet lag" - another condition that responds well to carefully timed use of bright light technology. |
 |
For nearly two decades, researchers have realized the therapeutic potential
of light as a treatment for Seasonal Affective Disorder ("SAD" or "winter
depression"), various types of sleep disorders, and jet lag. BioBrite ha
pioneered the development and marketing of light therapy devices based on the
work of scientists at the National Institute of Mental Health in Bethesda and
Thomas Jefferson University in Philadelphia. These products include light
visors, dawn simulators and programs designed to control individuals'
exposure to light. A brief summary of these products and their scientific
foundations follows.
Back to the top
Data from a large number of controlled clinical trials conducted during the
last fifteen years has repeatedly demonstrated the clinical efficacy of light
to treat SAD. Response rates have equaled or exceeded commonly used
antidepressant drugs. In 1998, the Archives of General Psychiatry published
the results of two large scale controlled trials conducted by over
three-to-four year periods demonstrating the positive results of light
therapy. The studies are even more compelling than earlier trials because of
the large numbers of patients involved and the use of ion generators as a
placebo control. The difficulty of finding a placebo for bright light led
earlier researchers to use lower intensity light as a placebo, and patient
response to this lower intensity light was relatively frequent. While it is
quite likely that the results occurred because lower level light is
therapeutic for some patients, later researchers searched for an effective
placebo. Clinical trials have convinced even the most skeptical scientists
that light therapy can be effective.
Back to the top
The BioBrite Light VisorT is the result of scientific study focused on
developing a mobile light source capable of delivering light therapy without
severely restricting movement or limiting activities of patients receiving
the therapy. The first light therapy devices were light boxes. Early models
were large, heavy, and awkward to move around. Current models have been
greatly refined and are much easier to transport; however, these devices
necessarily confine the patient to remaining adjacent to stationary boxes
while receiving light therapy. The restrictive nature of light boxes and
their concomitant effects on patients' quality of life led pioneering
scientists in the field, including Dr. George Brainard of the Thomas
Jefferson University College of Medicine, and Drs. Norman Rosenthal and
Thomas Wehr of the National Institutes of Health, to experiment with
head-mounted, battery- operated units capable of shining bright light into
patients' eyes without requiring the recipients to remain immobile.
BioBrite worked with these investigators to develop and market a
lightweight, easy to use, mobile head-mounted device, now trade-marked as the
BioBrite Light VisorT.
The Visor has been tested in controlled clinical trials. The earliest, in
1992, was in fact the largest single trial conducted in one season on the use
of light to treat SAD (Joffe, R.T., et. al.; Psychiatry Research, 46, 1993).
There were more than 100 patients involved. The response rate was good,
comparable to light boxes, however, some patients responded to low Visor
light intensities, raising the placebo issue. In retrospect, based on
current knowledge of the biological effects of light on humans, a feasible
argument can be made that under the circumstances of the experimental design,
low intensity light might have been effective for some people. Nevertheless,
a recent review of published data from light box trials and head mounted
units (HMUs) trials by two authoritative clinicians, led them to conclude
that HMUs produce response comparable in response rates similar to light
boxes for SAD (Seasonal Affective Disorder and Beyond: Light Treatment for
SAD and Non-SAD Conditions. Ed. Lam, R. W., American Psychiatric Press, Inc,
Washington, DC, 1998).
In evaluating clinical results of Visor trials, some investigators have
ignored, or are not aware, that four different models of the Visor have been
marketed by BioBrite. Each model incorporates improvements over earlier
models. Therefore, data from the first prototype model cannot fairly be
compared with data from more current models. Design problems with the Visor
principally relate to filling the field of vision of users with light, yet
not obstructing vision. This is a considerable challenge, considering
anatomical differences of human heads. The design of the relatively new LED
model has significantly addressed this problem. The light bar is located
further forward, directing light to the eyes at less of an angel, and an
array of LEDs provides a much larger area of light to the eyes. Dr. George
Brainard, Jefferson Medical College, an acclaimed expert on the biological
effects of light in humans, and Dr.Brenda Byrne a clinical expert on SAD, at
the same institution, have conducted controlled clinical trials to measure
the effect of the LED model Visor on melatonin ("the light hormone")
suppression in normal human volunteers. The data, which are currently in
preparation for publication, and were presented at the annual meeting of the
Society for Light Treatment and Biological Rhythms (SLTBR), 1999, clearly
demonstrated that LED Visor light can significantly suppress melatonin, an
important marker for the biological activity of light.
During the last SAD season, prominent clinical investigators at Yale Medical
School, and Jefferson Medical College, conducted an open trial of the LED
Visor in SAD patients. All of the 10 patients who completed the study
responded very well, and were pleased with the Visor. These results were
reported at the 2000 annual meeting of the SLTBR, and can be found in the
published abstracts, Vol. 12, of this society.
Back to the top
Several prominent scientists have conducted research on the biological
effects of gradually increasing light in wakening human subjects. Homo
sapiens evolved to waken by sunrise, which is now recognized as a powerful
biological signal. Experiments on normal human subjects and SAD patients
have demonstrated that dawn simulation advances circadian phase, and can be
efficacious in treating SAD (SLTBR, Abstracts, Vol. 12, 2000). A hypothesis
explaining a major factor in the etiology of SAD, which has been gaining in
popularity, is that patients are phase delayed. The BioBrite SunRise Clock
was designed to provide dawn simulation by an attractive, practical and
inexpensive devise. In a clinical trial of the Clock in high school students
conducted by Dr. Brainard and associates, it was found to be a popular and
effective wakening device SLTBR Abstracts, Vol. 10, 1998.
Back to the top
It has long been known that daylight is a critical signal in keeping the
"biological clock" (circadian rhythms) on time, consequently regulating the
sleep wake cycle in humans and lower animals. Two relatively common sleep
disorders, sleep phase delay, and sleep phase advance, have been recognized
in humans. These disorders may respond to bright light therapy. Sleep phase
delay, inability to initiate sleep, and to awaken at relatively normal times
is most frequently observed in adolescents and young adults, and may be
treatable with 2-3 hours of bright light therapy applied in the morning for
several days. Sleep phase advance, falling asleep, and wakening too early,
is common in the 65 years plus age group, and can be treated with bright
light applied in the evenings. These disorders can be complicated to treat,
and we recommend that people with these problems consult a sleep-medicine
specialist. A summary of relevant published data was published recently in
Sleep, Vol. 22, No. 5, 1999.
Jet lag is classified as a sleep disorder, which simply stated is the
inability of the biological clock of the jet-airplane-traveler to normally
reset rapidly to a new time zone. BioBrite has devised a program involving
the Light Visor that manipulates light to rapidly reset the biological clock.
The program is soundly based scientifically, and its efficacy is supported
by a number of antidotal reports by users. BioBrite has recently received a
Small Business Research grant from the National Institutes of Health to
support a controlled field trial of the program in normal human volunteers.
Melatonin has been reported to be helpful in preventing jet lag. However, a
large controlled field trial failed to demonstrate efficacy (Spitzer, R.L.,
et. al.; American J Psychiatry 1999; 156). Furthermore, melatonin is still
considered by scientists to be an experimental drug, and "over-the-counter"
preparations are not regulated by the FDA.
Back to the top |
|
