Last week we had the opportunity to experience some gorgeous sun after abnormal winter weather with many storms and lots of snow. The sunny days seemed to lift the mood of many of us including myself: I wanted nothing more than to be outside and soak up the rays of sunshine! Weather affects our mood immensely, which prompted me to research SAD. SAD stands for Seasonal Affective Disorder but is also used for Social Anxiety Disorder. The name Seasonal Affective Disorder was coined in 1984 by Norman E. Rosenthal at the National Institute of Mental Health Center. It is known as the following: winter depression, winter blues, summer depression, summer blues, or seasonal depression. SAD is essentially a mood disorder where people show severe depressive symptoms either during the winter or the summer. Most prevalent in Alaska at 9.9%, there can be heightened anxiety during these episodes and many symptoms are similar to that of depression. What makes this disorder different from other mood disorders? SAD occurs annually at the same time during the transition between seasons and lasts for the duration of the season; it can either be late spring and ends during the fall or can be late fall and end early spring, making summer and winter the targeted seasons. Instead of occurring as major depressive episodes or short periods of random depression, SAD occurs at the same time annually.
What are the causes of SAD? Researchers are still trying to target what exactly causes this seasonal disorder. They believe that certain hormones in the brain trigger changes related to attitude and mood during those times of the year and that SAD is highly related to these hormonal changes. For example, the possibility of a person having winter SAD would correlate with the effects of less sunlight and therefore less serotonin in the brain in the pathways that regulate mood. When these pathways don’t regulate properly because of the lack of production, depression results with accompanying physiological and physical symptoms (WebMD 2015).
Using EEG as a diagnostic tool in 2000 to explore neurophysiological profiles, Nina Volf and Natalia Passynkova studied the brains of patients with Seasonal Affective Disorder and how they compared with patients with other affective disorders. They wanted to find out how the brain was different than others with affective disorders through brain wave frequency. They tested 31 depressed patients with SAD and analyzed power in the delta, theta-1, theta-2, alpha, beta-1, and beta-2 frequencies. The results of their study confirmed that SAD subjects had an asymmetrical distribution of some of the frequency band’s activity in the parietal and temporal regions of the brain. This research provided evidence that there may be sub-varieties of affective disorders that cause these different depressive states within individuals. This would ultimately categorize them more specifically from a depressive disorder, indicating why people might feel certain levels of depression at certain times of the year (Volf & Passynkova, 2000).
As an additional note, it would be interesting to see why some people feel depressed during the summer months when they are exposed to sunshine.
Seasonal Affective Disorder (SAD)-Topic Overview. (n.d.). Retrieved April 24, 2015, from http://www.webmd.com/mental-health/tc/seasonal-affective-disorder-sad-topic-overview
Volf, N., & Passynkova, N. (2002). EEG Mapping in Seasonal Affective Disorder. Journal of Affective Disorders, 72, 61-69.