Your biggest obstacle can be yourself if you let it. The one person you can't tune out is your own mind. F.O.X.X. discusses overcoming the mental attribute and changing your internal monologue.
Song Credit: Lobo Loco "One More Night For You" http://freemusicarchive.org/music/Lobo_Loco/Natural_Flight/One_More_Night_For_YOU_ID_604