The American Journal of Psychiatry recently published a research study entitled “Outcomes One and Two Winters Following Cognitive-Behavioral Therapy or Light Therapy for Seasonal Affective Disorder”.
The research subjects were “adults with major depression, recurrent with seasonal pattern”. The research team divided them into two groups. One group received six weeks of “cognitive-behavioral therapy tailored for SAD”, while the other groups received six weeks of light therapy. The research team then tracked mid-winter depression levels for each group one year after treatement, then again two years after treatment. In the first year, they found no difference between the two test groups. Two years later, however, they found that the cognitive treatment group had fewer recurrences and less severe recurrences than the light treatment group.
Many media outlets reported on this study, with headlines like “Therapy Over Lamps for Seasonal Depression”, “Talk Therapy Trumps Light Therapy for Seasonal Depression” and “This Treatment Beats Light Therapy for Seasonal Affective Disorder”.
I have mixed feelings about this study and the subsequent media coverage.
On the plus side, this study adds to the overwhelming evidence that cognitive therapy works in fighting depression. Anyone struggling with depression can benefit from cognitive therapy, whether with a professional therapist or on your own.
On the other hand, the negative comments about light therapy in this media tempest are unwarranted. There is also overwhelming evidence that light therapy works. This research study showed clear benefits from light therapy.
Moreover, cognitive vs light therapy is a false choice. There’s no logical or logistical reason why someone can’t use both cognitive and light therapies as part of their depression-fighting strategy. There’s no reason why you can’t combine both these practices with other effective practices: physical exercise, improving your sleep hygiene, taking antidepressants, meditation and mindfulness, etc. There’s no one right way to fight depression.
For the purposes of a research study, it makes sense to divide subjects into groups receiving one type of therapy but not the other. That allows researchers to better isolate and measure the effects of each type. But there’s absolutely no reason for real-world depression sufferers to restrict their options like that.
One reason for light therapy’s second-place showing in this study: people stopped using it.
Patients have to “keep using the treatment for it to be effective,” [lead researcher Kelly Rohan] explained in a university news release. “Adhering to the light therapy prescription upon waking for 30 minutes to an hour every day for up to five months in dark states can be burdensome.”
The investigators found that, by the second winter, only 30 percent of patients in the light therapy group were still using the equipment.
In contrast, talk therapy is a preventive treatment, Rohan said. Once SAD patients learn the basic skills, the therapy has long-term effects that give them a sense of control over their depressive symptoms.
No argument there — to benefit from light therapy, you must continue to practice light therapy. The effects are short-term. This hardly seems like a reason to discourage people from using light therapy. Seems to me more logical advice would be, “If you benefitted from light therapy in the past, but you stopped using it and your depression worsened, you might consider making time for regular light therapy again”.
Personally I have never found sitting in front of the light box “burdensome”. I use that time to read books, listen to music, meditate, daydream, write in my journal. Sometimes I write out cognitive therapy exercises while lightboxing.