Catatonic depression basically shuts me down to the point where I'm not capable of doing anything, which is good because it's at these times that I realize that life is worthless, shitty, and without redeeming value. If I had any inertia I'd kill myself. This is the worst of the sin wave.
During the "normal depression" I just want to be alone and I find no joy in life. However anything that is escapist is appealing. I write stories, poetry, paint, and otherwise find outlets for creativity. It's all stuff you'd get really depressed if you saw, but there it is... the world deconstructed.
Then there are the times I'm feeling well. This is freedom like most people will never know. Remember that scene in Fight Club where he tells the guy that if he doesn't follow his dream he'll come back and kill him and then says something like "tomorrow his breakfast will taste better than anything you or I have ever eaten"? Well that's what it's like. The high of the sin wave. I can't even remember what depression is like... or even that I have it. All things feel good and life is wonderful. All my relationships have started in these phases. Hypo-manic, in a way.
I score in the top 99% for analytical thinking (for my age).
In the third grade I scored 152 on an IQ test.
I can solve most problems without actually thinking about the steps required. I just "know".
And yet, today I wanted to step in front of the subway train.