Finnish headset light therapy via the ear canal cut jet lag time in half in study

HumanCharger--Courtesy of Valkee

Researchers from Finland worked with startup Valkee to unveil a bright light headset to treat seasonal affective disorder in 2010. Now it's released placebo-controlled, randomized data about jet lag reduction for its CE-marked headset dubbed the HumanCharger.

This is the first placebo-controlled trial ever conducted for a bright-light device, the company said. The data may be designed, at least in part, to address allegations widely publicized online that the company's product is a scam.

The study compared a 25-patient treatment group, which recovered from jet lag in three or four days--about half the time as a 30-person placebo group, which required more than 7 days. The treatment group received non-ocular bright light through earphones directly into the ear canals and onto the photosensitive brain regions for four daily 12-minute light dose sessions during transatlantic travel across 7 to 10 time zones and for up to 7 days after arrival at their destination.

Study participants were examined using scales to judge subjective sleepiness, as well as POMS scores for feelings of fatigue, inertia, and forgetfulness. They flew from Finland to North America for at least a week with a time difference of 7 hours to 10 hours. The HumanCharger device received a CE mark in April.

"This study conducted under field conditions shows that an alternative route of light administration, i.e., transcranially, significantly reduces jet lag symptoms," summed up the researchers in a paper in the journal Aerospace Medicine and Human Performance. By the end of the post-flight week, 83% of the treatment group was free of jet lag symptoms, while only 55% of the control group were.

Researchers did acknowledge that further studies are needed on the effect of transcranial bright light on the body's circadian phase, for which the minimum core body temperature is a market, as well as in westward, rather than eastward, air travel.

The device has a free accompanying smartphone app to alert users to the correct timing for the light exposure. The HumanCharger retails for $279 on Amazon.

- here is the release
- and here is a recent Smithsonian article on the HumanCharger

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