My approach to music is to start with a rhythm track, which helps to keep the beat, of course. From there, I either work out the chord progression, or a bass line. Adding feeling to a song comes when I imagine who or what I am singing, or composing about.
I enjoy writing out the notes to each instrument's part.
There are a lot of stereotypes of artists. However, I can say that many creative people that I have met tend to be on the quiet side. I think this has to do with the process of creating. Some say, we are 'deep thinkers.' Imagine seeing a pearl on the bottom of the ocean and diving in to get it.
That's us when we get an idea. I believe the term is "in the zone."