Science Buddies: "Ask an Expert"

Hi!

I'm new to science buddies and science fairs in general, but I've got a project in mind for a fair that is to take place next March. I'm researching quantum dot white LEDs, and because they produce a natural, warm white light, I was thinking that I could do an experiment relating to light therapy. I plan to compare its stress-reducing effects with normal LEDs or conventional light therapy methods. I'll probably conduct the experiment over winter vacation, when there isn't much light and people are prone to mild Seasonal Affective Disorder.

However, I'm not sure how to go about doing this. Is it practical to make my own quantum dot LED with purchased magic-sized quantum dots (which is what I'd rather do), or should I just purchase one? Also, how can I measure the stress of volunteer people easily, if I decide to have a group of people use QD LEDs and a group use normal ones? Using mice is another alternative but I don't want to get into experiments with vertebrates because I'm not too sure about the rules for this science fair. I've always been interested in depression and those kinds of disorders, but they're hard to measure.

Any advice on how to do these stress-measuring experiments would be very helpful.

Thanks!

Hi,

I like your question because it makes me wonder how we can know that lighting in a room actually affects mood. I am sitting now in my home office with a special "full spectrum" light. It's raining outside and I'm surrounded in white light. I don't have SAD -- I just like this light. Maybe it's simply bright and that makes it easier to work?

You raise two questions -- about acquiring the light source for the experiment and setting up the experiment itself. I don't know the tradeoffs you're facing in terms of difficulty and cost. If you have information about making a QD LED, could you share that with us, so we can help evaluate what's involved?

My own first idea was to search for information about QD LEDs. I notice a company, QD Vision in Watertown, MA (http://www.qdvision.com/contact/), seems to have developed the technology. Maybe if you called them (and persist to get the right person), you might find that they are willing to donate a light for your experiment or an engineer in the company can help you decide whether to purchase or make a light source. I don't know how you learned about QD LEDs -- if it's from someone who works in that area, they might be able to help.

As for the experiment itself, I'm not an expert in that area either, but I do know that companies and research centers conduct experiments like the one you describe. I did a search on "SAD light therapy reviews" and found the Center for Environmental Therapeutics (http://www.cet.org/) and the MayoClinic (http://www.mayoclinic.com/health/light-therapy/MY00195 -- click to expand the references section) have conducted or commented on studies. My search also came up with publications such as this -- http://ajp.psychiatryonline.org/cgi/con ... /162/4/656

So my idea would be to research what studies have been done before about SAD with full-spectrum lighting. See what is online, and if you have questions, contact these research groups (or the author of papers you find). The MayoClinic article in particular claims that there are measurable affects after just one week with 15-30 minutes per day -- that's very encouraging for your project -- how do they know this?

How were the experiments set up? How did they measure the effects? Does time of day matter (e.g., early evening makes more of a difference than middle of the day treatment)? Is a questionnaire the only evaluative tool? Reading about these studies will give you ideas for what you can do, plus also you will learn about criticisms of the work. Perhaps you can find a way to improve what's been done before or replicate it with different groups of people. For example, is there a measurable effect for people who don't have SAD?

I hope this has been helpful. Please write back if you have more questions and perhaps others on this forum can provide suggestions.

Bill