Ear's an idea: The effects of seasonal¹ affective disorder² could be combated by channeling light to the brain down the ear duct

As the nights get longer, those who suffer from the winter blues³ will be planning ways to escape to the sunshine.

But there may be a much simpler way of cheering yourself up... simply shining a bright light into your ear canal.

Up to one in four Britons suffer from seasonal affective disorder, with seven percent of the population having full-blownSAD.

It is caused by the brain not receiving enough daylight which is needed to trigger serotonin, a hormone⁴ that regulates mood. Symptoms range from mild lethargyto depression and insomnia⁵, but a cure might be in sight.

Two clinical trials, run by Valkee - who make a device that can shine light into your ear - and the University of Oulu in Finland, have found that carefully targeted light can help prevent the condition.

Juuso Nissil , Valkee's co-founder and chief scientist said: 'We presented earlier that the human brain is sensitive to light.

'These two clinical trials demonstrate that channeling bright light via ear canal into brain's photosensitiveareas effectively prevents and treats seasonal affective disorder.'

The University of Oulu reported that in their first study, 92 percent of the patients with seasonal affective disorder achieved full remissionafter a month of daily eight-to-12 minute doses of light from the Valkee.

Timo Takala, chief physician at the Oulu Deaconess Institute said: 'These two trials show that bright light channeled into the brain via ear canal is an important future method to treat seasonal affective disorder.'

Valkee launched its bright-light headset in August 2010. It is classed as a medical device under EU regulations.

The device channels bright light direct to the brain via the ear canal to prevent and cure depression, mood swings and even circadian-rhythmdisorders such as jetlag.

It costs ￡185 and looks like an iPod - only the earphones emit light rather than sound.

随着黑夜变长，那些患冬日抑郁的人要开始考虑想办法逃往阳光地带了。

不过也许有一种简单得多的方式能让你的心情好起来——只需将一束亮光射进你的耳道就行了。

多达四分之一的英国人会患上季节性情绪失调，7%的英国人季节性情绪失调很严重。

这种失调的病因在于大脑没有接收到足够的日光来产生所需的血清素，这种荷尔蒙可以调节心情。症状较轻的表现为轻微的嗜睡，严重的则表现为抑郁和失眠，不过我们可能就要看到治疗之道了。

Valkee公司和芬兰奥卢大学联合开展的两个临床试验发现，目标精确的亮光有助于预防这一病症。Valkee公司生产一种可以将光线射入人耳内的仪器。

Valkee公司的共同创立者和首席科学家朱索 尼西拉说：“我们早些时候已经向人们展示，人的大脑对光线很敏感。”

“这两个临床试验证明，将亮光通过耳道照进人脑的感光区域可以有效地预防和治疗季节性情绪失调。”

奥卢大学在他们的第一项研究的报告中称，92%的季节性情绪失调患者在接受Valkee公司一个月的光线治疗（每日8到12分钟）后已经完全康复。

奥卢迪肯尼斯研究所的主任医师蒂莫 塔卡拉说：“这两个试验表明，通过耳道照进大脑的亮光是未来治疗季节性情绪失调的一个重要方法。”

Valkee公司于2010年8月推出亮光耳机。根据欧盟规定它被归入医疗器械类。

这一仪器将亮光通过耳道直射入大脑，从而预防和治疗抑郁、情绪波动以及飞机时差反应等昼夜节律失调的症状。

这种亮光耳机售价185英镑，外形和iPod相似，只不过耳机所发出的是光而不是声音。