Many readers in the Northern Hemisphere are likely already starting to experience seasonal affective disorder, appropriately enough known as SAD. For those people fortunate enough not to be familiar with it, SAD is a mood disorder that is brought on by the shorter day-length experienced in winter - less sunlight results in gloomier people. One of the most common treatments involves regular exposure to bright artificial lights, that appear to psychologically serve the same purpose as sunlight. Now, one might assume that such light therapy would require that people see the light. According to the Finnish designers of the Valkee device, however, light also does the trick if you shine it up your ears.

The invention is based around the assertion that not only are our visual systems photosensitive, but so are our brains themselves. More specifically, there are apparently 18 sites in our brains, where OPN3 photoreceptor proteins are located. These regions will supposedly react favorably to exposure to light, even when that light is filtered through tissue and bone.

The Valkee itself looks a lot like a personal music player, complete with earbuds. Instead of emitting music, however, these buds contain fiber optic lights. By turning the device on and sticking the glowing fibers in your ears for about ten minutes a day, it is claimed that your brain will receive enough light to send the SAD packing.

Does it sound like quackery? A great deal of people would certainly say so. Not among those people, however, would be a group of scientists from Finland's University of Oulu. In two clinical trials, they had people with severe SAD use the device daily, for 8 to 12 minutes a day. Afterward, when those people completed a BDI-21 questionnaire (a standard for assessing depression), it was found that 92 percent of the subjects in the first trial had completely recovered.

The information presented by the company is definitely somewhat difficult to sort out, although it appears that the results of the second trial were similarly encouraging. A placebo group was included in at least one of the trials, to ensure that people weren't feeling better merely because they expected to.

All told, it's still pretty hard to know what to think. If you want to give it a try, the Valkee can be purchased from the company website for GBP185 (US$294).