"train of thought" saw limited release as the third single in europe. it was not released as a 7" in the united states but received rock radio play and a set of remixes again made the dance charts. waaktaar based the lyrics for this song on existentialist authors and poets gunvor hofmo, knut hamsun and fyodor dostoevsky, his favourites at the time. it was a-ha's third consecutive top 10 single in the united kingdom and ireland, reaching #8 and #5 respectively, and charting well in germany and sweden. world sales hit 500,000 copies.