Inspired by the audience response to Dream Theater's heavier songs while on tour,[5] in the Chaos in Progress documentary, Portnoy says that they wanted Train of Thought to be a "balls to the wall" album with heavier, darker riffing, exposing them to a number of new metal fans. The album was written in three weeks.[6] It was engineered by Doug Oberkircher and mixed by Kevin Shirley.[7] Most of the album was played in concert for the Live at Budokan DVD. All songs from it have been played live to date.