They can. But most of the time I feel like my moods determine what music I listen to to begin with. If I'm mad, I want to listen to angrier music. If I'm sad, I want slower sad music. If I'm in a good mood, well I'll listen to everything. When I'm upset, I just can't get myself to listen to anything upbeat or positive. My mind rejects it every time. I mostly listen to my iPod to know what I'm listening to..