How To Use Light Therapy?

I've been reading through the DSPS section of this website. In the main article, the author mentions light therapy as a way to treat DSPS. He says that for it to be effective the light would have to be at least 10,000 lux, and you should have the light in your periphery because doing so causes the light to activate more photoreceptors in your retina.

Firstly, is what I said above true? Did I misunderstand anything I read?

Secondly, could you talk more about how to use light therapy as a treatment for DSPS? Specifically, I'd like to know when to expose yourself, for how long, at what intensity etc. I anticipate that the answer will involve saying that it depends on the person and circumstances. If so, could you 1) give general guidelines and 2) talk about how the specifics and circumstances of the person affect how you use light therapy as a treatment (ex. if you have good sleep hygiene, typically sleep from 5AM to 2PM and want to sleep from 12AM to 8AM; hopefully I didn't get my AM and PM confused)

Finally, are there any good light box products that you would recommend?

Thanks a lot for your help.

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Kevin: Hey, thanks for your question. Your description in the first paragraph sounds like you interpreted those elements from the article correctly. 10,000 lux is what I've heard in class to be the ideal minimum strength of the light to be effective, and you want it in your periphery so that it's incidental to your activity and focus, just like sunlight is normally during the day.

Artificial light (computer screens, TV, lights on at night) makes it easy for our brain to think that night time is actually part of the day still. The idea behind using a light box to shift circadian rhythms is to essentially trick your body into realizing that daytime starts earlier in the morning than it thinks, so it should adjust when it gets tired at night accordingly.

The way you do this is by exposing yourself to bright light in the morning, progressively closer to your target wake time. Meanwhile, you also want to stay away from bright artificial light deep into the night.

So for shifting a delayed sleep phase backward, you want bright light in the morning upon waking (or even better, before waking). On the flip side, for shifting an advanced sleep phase forward, you want bright light in the evening or early night.

Light boxes are the real professional way to go about shifting your circadian, but I find for me personally that sleeping with the curtains open is usually good enough to shift me in a few days. With my curtains open, bright sunlight enters the room around 7 or 8AM. If I'm still sleeping at the time, the light can still make its way through my eyelids to communicate with my brain, letting it know its daytime. Some light boxes I believe come with timers that lets you control when they come on and turn off, so alternatively you'd probably be able to achieve a similar effect with a user-friendly light box.

I've never used one myself, so I don't have any recommendations on a specific product. Has anyone out there reading this found a light box that they have found particularly useful? Furthermore, does anyone have any additional commentary or questions about light therapy in general? Feel free to post any thoughts using the comments link below.

Warmly,
Kevin

(Please keep in mind that I am a student of sleep science and not a medical doctor. Please take any thoughts I give with my background in mind.)