Taylor Swift`s new song about ex-boyfriend Harry Styles

London: Singer Taylor Swift has admitted that her latest song `I Knew You Were Trouble` is about ex-boyfriend Harry Styles.

The 23-year-old performed her single at last month`s Brit Awards and hinted that it was easy to channel the emotion knowing Styles was in the audience, reported Contactmusic. "You`re balancing the analytical side of your brain, which is telling you where to go and how to go there, with the other side of your brain, which is saying, `Feel everything you`re singing, and show it on your face. Feel everything exactly as you felt it when you wrote the song`," Swift said. Asked how she felt knowing Styles was watching the performance in the audience, she replied, "Well, it`s not hard to access that emotion when the person the song is directed at is standing by the side of the stage watching." PTI