Naked Science Forum

Life Sciences => Physiology & Medicine => Topic started by: davekm on 08/06/2012 16:36:52

Title: Does light exposure affect sleep patterns?
Post by: davekm on 08/06/2012 16:36:52

I have read that exposure to blue light two hours before sleep, reduces melatonin.

Which of the following scenarios would produce the least blue light exposure?

Bed lamp + book
Backlit e-book reader
Clip on reading light. <link broken and removed by moderator>

Title: Re: Light eposure and it's effects on sleep
Post by: CliffordK on 08/06/2012 21:45:11

A similar question was presented here:
http://www.thenakedscientists.com/HTML/content/qotw/question/3398/
http://www.thenakedscientists.com/forum/index.php?topic=43826

I've never used an E-Reader, but have used a computer screen. 

If one turns off the lights, and only illuminates the book with either a backlit e-reader, or a page light for printed media, then the overall amount of light entering the eyes would be minimal. 

However, the light entering the fovea may remain high as one concentrates on the page.  Does that make a difference?  Black on white, or white on black text?

I've tried reading by a kerosene lamp.  They certainly don't put out much light, at least when adjusted low.  How did people ever read by them in the past?

Anyway, I would think that a dim backlit e-reader or a single page light would be good for maximizing the dark and minimizing the stray light.  Perhaps it would also be less distracting to others sharing the room, with an e-reader potentially being virtually silent.

How easy is it to adjust the light intensity on the E-Readers?  I know I rarely adjust my computer monitor intensity.

Title: Re: Light eposure and it's effects on sleep
Post by: davekm on 08/06/2012 21:48:57

Thanks. I don't own a e-reader. Just thinking about it, due to the ability to increase text size.