Yeah, it's rarer. I think it's believed to be caused by heat and humidity, instead of light deficiency. I suspect I may have both types. I am heat, humidity, and light-sensitive. I always get depressed when it starts to get hot, knowing a stretch of months of misery in front of me. It also means the return of bugs to mess w/ my bug phobia.
It's no wonder my mood is so bad in the spring. My light levels aren't back to normal before the heat and humidity show up, I'm getting an overlap.
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