美国国家公共电台 NPR Apps Can Cut Blue Light From Devices, But Do They Help You Sleep?

 

DAVID GREENE, HOST:

OK, now let's talk about some light that is probably not as good for you. This is the light coming from your smartphone or other screens. It's known as blue light. And it can really interfere¹ with your sleep. Some people are using apps to filter out some of that blue light. As for how these apps actually work, NPR's Jon Hamilton reached some scientists.

JON HAMILTON, BYLINE²: The first person I called is Lisa Ostrin at the University of Houston College of Optometry. She studies the effects of blue light on sleep. She also owns an iPhone. And every iPhone comes with an app called Night Shift that lets you filter out blue light. So I ask Ostrin, do you use it?

LISA OSTRIN: Yes, I do.

HAMILTON: Ostrin says without a filtering app, cell phones and tablets expose people to a lot of blue light.

OSTRIN: Especially as people are laying in bed and have their screens just a few inches from their face before bedtime.

HAMILTON: And Ostrin says all that blue light prevents photoreceptor cells in the eye from triggering the release of an important hormone³.

OSTRIN: Normally, when the sun goes down, and the lights turn off, our body releases melatonin, which helps us get a nice, restful sleep. But when we have all this artificial light on, it's tricking those photoreceptors into thinking it's still daytime.

HAMILTON: Ostrin's own research has shown that it's possible to prevent this. She had 21 people put on special glasses after sunset each day to filter out blue light.

OSTRIN: So, essentially⁴, we block the input⁵ to those photoreceptors that tell our body it's still daytime.

HAMILTON: And it made a difference.

OSTRIN: What we found was a dramatic increase in their nighttime melatonin levels after two weeks of wearing these glasses.

HAMILTON: Participants also reported better sleep. To get another perspective, I called Brian Zoltowswki at Southern Methodist University in Dallas. Like Ostrin, he studies blue light in sleep, and he owns an iPhone.

BRIAN ZOLTOWSKI: I am talking to you on an iPhone right now. And I actually am not a Night Shift user currently.

HAMILTON: Zoltowski says he did use the filtering app. He also took steps to reduce the blue light coming from other screens during the evening. And he says that made every image look kind of orange.

ZOLTOWSKI: So I'm looking at an orange screen, watching a video, realizing I'm also drinking a cup of coffee. And it started to make me wonder then why I'm actually trying to, you know, decrease the amount of blue light when the caffeine that I'm drinking in my cup of coffee is probably having a larger effect on my sleep quality.

HAMILTON: Also, he really didn't like all those orange screens.

ZOLTOWSKI: I'm willing to take the blue light exposure for the improved quality of the images.

HAMILTON: Zoltowski adds that devices are just one source of blue light. Others include indoor lighting⁶ and street lights. So he says a filtering app may not be worth it, especially if you're already getting a good night's sleep.

ZOLTOWSKI: But if you suffer from sleep problems, and you've tried other things like eliminating caffeine later in the day, this is something that you can add to your kind of repertoire⁷ of making sure that you're doing everything you can to promote a healthful sleeping environment.

HAMILTON: Zoltowski says you might also just give up screens entirely⁸ around bedtime. At least one study found that people got more sleep when they switched from electronic readers to printed books. Jon Hamilton, NPR News.

(SOUNDBITE OF MOKHOV'S "EUPHORIC MAGIC")

1 interfere   

v.(in)干涉，干预；(with)妨碍，打扰

参考例句：

• If we interfere, it may do more harm than good.如果我们干预的话，可能弊多利少。
• When others interfere in the affair,it always makes troubles. 别人一卷入这一事件，棘手的事情就来了。

2 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

3 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

4 essentially   

adv.本质上，实质上，基本上

参考例句：

• Really great men are essentially modest.真正的伟人大都很谦虚。
• She is an essentially selfish person.她本质上是个自私自利的人。

5 input   

n.输入(物)；投入；vt.把(数据等)输入计算机

参考例句：

• I will forever be grateful for his considerable input.我将永远感激他的大量投入。
• All this information had to be input onto the computer.所有这些信息都必须输入计算机。

6 lighting   

n.照明，光线的明暗，舞台灯光

参考例句：

• The gas lamp gradually lost ground to electric lighting.煤气灯逐渐为电灯所代替。
• The lighting in that restaurant is soft and romantic.那个餐馆照明柔和而且浪漫。

7 repertoire   

n.(准备好演出的)节目，保留剧目；(计算机的)指令表，指令系统， <美>(某个人的)全部技能；清单，指令表

参考例句：

• There is an extensive repertoire of music written for the flute.有很多供长笛演奏的曲目。
• He has added considerably to his piano repertoire.他的钢琴演奏曲目大大增加了。

8 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。