Columbia University Medical Center
Ranked #1 in Psychiatry
U.S. News & World Report
Ranked #1 in Research Funding
National Institutes of Health
NewYork-Presbyterian Hospital The University Hospital of Columbia and Cornell

Ask the Experts


I work in a cubicle with 6-foot high panels, so I don't get any natural light during the day. I have just started using a 10,000 lux light box upon waking. Would it be helpful to also use a desk lamp version of the light box for a short period of time while I am at work?

Answered by: Michael Terman

You don't say what you're trying to treat with light therapy, so let us presume that: (a) you are feeling depressed and fatigued; (b) you are having trouble waking up in time to get to work; (c) you are not taking any daytime stimulant medications; and (d) you are timing your light therapy according to the Automated Morningness-Eveningness Questionnaire at The first question is whether this is working well for you. Ideally -- actually, most often -- the benefit of early morning light therapy lasts all day and does not require supplementary exposure. If you're using the light for 30 minutes (for example), but still slumping badly in the afternoon, a dose adjustment to 45 minutes may do the trick. Sometimes, however, slumping does perist. In that case, you may be able to snap out of the slump with even a brief (for example, 10-minute) light therapy session in the afternoon, just as you feel the slump coming on. You should use the same kind of device at your desk as you do at home: two recent, well-designed, attractive models are the Day-Light ( and the LumiVera (