Shining light in the ears may alleviate SAD symptoms

March 7, 2012 by Lisa Zyga report
Light shone in the ears reaches light-sensitive proteins on the brain's surface. Image credit: Valkee

(Medical Xpress) -- Millions of people experience depression and lower levels of energy in the winter due to seasonal-affective disorder (SAD), or the “winter blues.” Since the disorder is thought to arise due to a shortage of natural light, one common form of treatment is light therapy, in which the person sits in front of a bright, full-spectrum light at certain times of day. But the effectiveness of light therapy has been unclear, and now researchers from Oulu, Finland, think they know why: light-sensitive regions of the brain may actually play a larger role in SAD symptoms than those in the eyes. For this reason, they’ve designed earphones that shine light through the ear canal to light-sensitive proteins on the brain’s surface, with encouraging results.

Juuso Nissilä, a physiologist at Oulu University, designed the device after his research revealed light-sensitive proteins on the surface of animal brains. Investigating further, he discovered that a light-sensitive protein found on the human retina, opsin-3, is also located in 18 separate regions of the human brain. Further, the proteins are abundant in areas involved with the production and storage of the neurotransmitters serotonin, melatonin, and dopamine, which are involved in mood and sleep. Nissilä explains that these proteins in the brain, not those in the eyes, may have the greater impact on mood fluctuations associated with daylight changes. And the may be the best way to reach these areas.

The bright light headset contains white LEDs that produce wavelengths close to that of sunlight. Image credit: Valkee

“Shining into the brain through the ears is a far better way to deliver bright than staring at a lamp,” Nissilä said. “There’s no evidence that shining light in your eyes has any effect on mood, whereas we now have evidence that these brain-surface proteins are involved. Bone is actually quite a good transmitter of light - put a torch inside a skull and you’ll see the beam very clearly - so I now think that it’s the light reaching your brain surface through your skull which is the important factor.

“There are two good reasons to use the ears,” he added. “The first is that the skull is thin around the ear canal area, and a very good proportion of the light gets through. The second is that there are comparatively few blood vessels on the surface of the brain at that point,” and blood strongly absorbs light.

In order to develop a bright light headset, Nissilä co-founded a company called Valkee. The devices they make contain a white LED in each earphone that produce wavelengths close to that of sunlight, although the company says that the bluer wavelengths have the strongest effect.

Researchers at Valkee have recently published the results from their first clinical trial in the journal Medical Hypothesis. In the trial, patients received 8-12 minutes of 6.0-8.5 lumen bright light daily into both ear canals for four weeks. The results showed that 92% of the patients with severe SAD symptoms achieved full remission when measured by a self-rated questionnaire designed for psychological studies, and 77% as measured by a psychiatrist-rated questionnaire. Given the positive results, the researchers plan to further investigate the therapy with randomized placebo-controlled and dose-finding study designs.

The headset is commercially available in Europe for £185 ($290), but cannot yet be shipped to the US. On Valkee’s website, the company claims that the headset can treat mood conditions like anxiety, tiredness and reduced cognitive performance due to SAD. The researchers are also investigating whether the device can be used for jet lag and migraines.

Explore further: Winter blues see the light

More information: Markku Timonen, et al. “Can transcranial brain-targeted bright light treatment via ear canals be effective in relieving symptoms in seasonal affective disorder? - A pilot study.” Med Hypotheses (2012), DOI:10.1016/j.mehy.2012.01.019

via: The Engineer

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3 / 5 (2) Mar 07, 2012
Pretty smart to set the company up before the final results arrive. That way you can establish a presence on the market before the effect is declared bunk, and the initial marketing push creates a popular following to the idea regardless.

Fantastic news travel faster than the truth that follows.
1 / 5 (2) Mar 07, 2012
Yes, will there be a study on whether this therapy actually works? :-)
1 / 5 (1) Mar 07, 2012
So does this have anything to do with that light bulb that pops up when someone has an idea?
not rated yet Mar 07, 2012
RIDICULOUS price. Two LEDs and a battery?
Daylight LEDs retail at six bucks each.
1 / 5 (2) Mar 07, 2012
But hey, these are Very Special Extra Continuous Smooth Non-interrupted-spectrum Real Daylight Leds, manufactured to their specifications, in small series!

It pays to be careful with dosage and quality even if you are using snake oil.
1 / 5 (2) Mar 07, 2012
"Shedding light" acquires a new twist.
not rated yet Mar 07, 2012
Now fellows, don't conclude this is a scam before the rumors are be rumors.

By the way, you could rig up something like this yourself for about twenty bucks. Buy a couple USB reading LED's, then strap them to an old set of ear phones. Guaranteed the savings will relieve depression, and all your friends will giggle with glee.
4 / 5 (1) Mar 07, 2012
Just tried this experiment minutes ago on myself.

All that resulted was the light providing an extremely subtle sensation of warmth in my left ear, while a beam of light simultaneously began emanating from within my right ear thus causing the emanating light to reflect on the wall 2 feet away.

I will now attempt to interpret the results and write a paper!

not rated yet Mar 08, 2012
They have also found that reaction rate of ice hockey players improved by ~20% during winter time by using ear lights. For me, it is still hard to believe this really works, but I may as well give it a try next winter. Don't know if I'm going to do it with these expensive devices, but rather try something home built device.

1 / 5 (2) Mar 08, 2012
This one has actually been around for a wile, but apparently they just released some "research".
If I understand correctly from this article, they haven't done any placebo studies yet, so the effect they describe could be a placebo effect, or indeed an effect of a slight increase in temperature, not the light.
I'll wait for the randomized clinical trials to be completed before jumping to conclusions...
5 / 5 (1) Mar 08, 2012
Good news, people, Opsin-3 is also found in large quantities in testes. Now nobody will see your goofy ear lights because they'll be down your pants.
5 / 5 (1) Mar 10, 2012
Ah, they've got that ear caught in the headlights look!

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