If I am really listening and thinking about what a person is saying and also thinking of how to reply, I have a habit of looking down. As a child I was very shy and had difficulty maintaining eye contact for any length of time because it caused anxiety. I thought I had outgrown this habit until my son started asking me what I found so interesting on the floor whenever he talked to me.
My son has never had any trouble making eye contact and he is much smarter than I ever was. He is even able to look his acting teacher straight in the eye when she is yelling at him and then calmly explain why he did what he did.
