With the weather getting colder and the days becoming shorter, some people are noticing they have less energy and aren't feeling as positive as they usually do. This type of depression is known as seasonal affective disorder (SAD).
Researchers aren't yet clear on what causes SAD, but it's likely to be complex. Some research suggests it could be due to a malfunctioning hypothalamus (下丘脑功能不全) or producing too much melatonin (a hormone which controls our sleep-wake cycle). Some researchers theorize it could also be due to having a disrupted circadian rhythm（昼夜节奏混乱）. For example, some research has indicated that women may be more likely to experience SAD — though, due to a lack of specific research, it's uncertain whether these gender differences really exist and if so, why.
Some people notice that their symptoms start to improve when the seasons begin to change and spring approaches. For people with SAD, the main recommended treatments include psychological treatments or taking medicine. Research shows that cognitive behavioral therapy (CBT) is an effective treatment for SAD. Given it's still an emerging therapy, research on it remains inconsistent with other treatments.
Aside from seeking professional help, there are a couple of other things that people can do to help them cope with SAD during their day. The researchers of the study had participants either go for a daily one-hour outdoor walk or use a low-dose artificial light box for 30 minutes per day for a period of one week. The participants who went for a daily walk showed significant improvements in all depressive symptoms, compared to those exposed to artificial light.
A. Colder weather and less daylight may have you feeling a bit more down lately.
B. Research also shows that lifestyle factors can play an important role in both causing and managing depression.
C. According to one study, getting more natural light during the day may help improve symptoms.
D. Of course, there may be other factors at play too.
E. But this doesn't mean that there aren't many things people can do during the winter months to help them cope with their symptoms.
F. While these feelings may be temporary for some, around one in three people consistently struggle through the autumn and winter months.
G. Light therapy is also currently being investigated as a treatment for SAD.