Yeah Yeah Yeahs included a rapper on their new album to make it more fun.

The 'Heads Will Roll' band have a track with Dr. Octagon on fourth record 'Mosquito', and singer Karen O was keen to include him as they wanted to embrace new styles for the record.

She said: ''We really wanted to have as much fun as we could with the writing and collaborating with people and push ourselves to do things we hadn't done before. I've always fancied a rapper to be on a YYYs track so we got him to do it.''

The band also worked with LCD Soundsystem musician James Murphy on another track, which has a ''trippy'' sound.

Karen added to NME magazine: ''It's probably one of the dancier ones on the record. But it's also kind of like doing nitrous in a bat cave. It's spooky. It's got a dancey beat but its generally a bit trippy.''