Kylie Minogue's hit Can't Get You Out Of My Head has topped a poll to find the world's catchiest song.
Scientists at the Institute of Brain, Behaviour and Mental Health in Manchester, England carried out a survey of 700 test subjects to establish which track registers strongest in the memory.
They hope the study will provide clues about why humans remember music and will help to find new ways to aid those suffering from diseases such as dementia.
Musicologist John Ashley, who is working on the project, says, "Understanding catchy music is about much more than just a recipe for next week's number one hit: It's the key to understanding why musical memories last a lifetime."
The survey placed Robin Thicke's Blurred Lines in second, Daft Punk's Get Lucky in third and Abba's Sos in fourth.
Minogue's 2001 hit topped the charts in dozens of countries.