Seasonal affective disorder is classified by symptoms such as fatigue, hypersomnia and overeating which only occur during the winter months. However, according to Dr. Mary Wells, associate professor of Psychology at Sinclair Community College, it is not its own disorder.
“Seasonal affective disorder isn’t a true disorder,” she said. “Seasonal affective disorder is the popular term we use to describe these winter depressions, although you can find manias during the summer. We think of seasonal affective disorder as being a winter sort of thing, but actually the way we diagnose it would be major depression or bipolar disorder with a seasonal specifier, so there’s not technically a diagnosis of seasonal affective disorder.”
SAD affects those living with bipolar disorder and depression. Those coping with these disorder can go through periods of insomnia or hypersomnia, however during the winter months, psychologists have found that those with a seasonal component to their disorder are more likely to suffer from hypersomnia; they may also generally feel more fatigued.
“It impacts appetite to a greater degree than what we see with straight-forward depression,” she said. “With regular depression, it can either be eating too much or too little, but with the seasonal depressions it tends to be that we eat more.”
She said psychologists can see different occurrence rates with SAD over different parts of the globe.
“The farther you are from the equator, the higher the prevalence rates are,” she said. “So its thought to be [related to] the amount of available daylight; the farther we get from the equator, the more variance we have. So if we get to a place like Alaska, in the winter you’ll have some periods of time where you’ll have no daylight at all. When you’re at the equator, you have much less variation. In lots of tropical regions, we don’t see nearly these sorts of seasonal patterns.”
Norman E. Rosenthal, who originally defined SAD, said psychologists may have seen a greater prevalence rate this winter than in the past due to the weather being more severe.
“It is really thought to be related to not getting enough sunlight,” Wells said. “Even if it’s a bright, sunny day outside, if it’s -18 degrees we’re still not going outside. Really low temperatures keep us inside more, and there’s more of a cloud coverage during winter as well.”
She said treatment options include aerobic exercises and light therapy.
“They will sit people down in front of these specialized wide-spectrum lights, they mimic sunlight without frying your eyes with UV rays, and people will sit in front of those as a prescription … They do prescribe antidepressants, but the light therapy’s are just as effective, and they work more quickly,” she said. “[They usually sit in front of the light] about a half hour a day, and it’s at a particular time of the day as well. You couldn’t do this at eight o’clock at night, you’d probably mess up your circadian rhythms, so you have to be careful of doing this light therapy at the right times.”
An individual’s circadian rhythms are the patterns that determine their sleep and wake schedules.
“When daylight hits your eyeball, it gets transduced into your retina and the signal gets passed into the brain … [including the] pineal gland, [which] produces melatonin, which is a transmitter hormone related to serotonin and helps regulate mood and wakefulness, a lot of different types of behaviors. Melatonin is specifically related to regulating our circadian rhythms. The input of the light reduces melatonin, [in] darkness, melatonin is no longer suppressed, [you start] producing melatonin, it goes through the body and you get sleepy,” Professor of Psychology Anne Soltysiak said, adding that lower levels of sunlight, can impair your circadian rhythms.
As we enter the spring season, Wells said those living with SAD may feel relief.
“Once we start getting into the spring months, there is more available daylight and we see more of a natural treatment, in terms of the light,” Wells said.