Personally I believe that depression is caused when you're not doing what you want (or you're not aware of what you want). By not doing what you find rewarding

Personally I believe that depression is caused when you're not doing what you want (or you're not aware of what you want). By not doing what you find rewarding your brain doesn't have enough dopamine running through your system. It's still a concept in development so I'm open to any counter arguments.