NME/Press Association reports that researchers at London's Goldsmiths University compiled data about what makes songs memorable, observing thousands of volunteers listening to a playlist. Based on what they saw, the five catchiest songs ever are, apparently: "We Are the Champions" by Queen, "YMCA" by the Village People, "Fat Lip" by Sum 41, "The Final Countdown" by Europe" and "Monster" by the Automatic.
Of the results, music psychologist Dr. Daniel Mullensiefen explained: "Every musical hit is reliant on maths, science, engineering and technology; from the physics and frequencies of sound that determine pitch and harmony, to the hi-tech digital processors and synthesizers which can add effects to make a song more catchy." Of course, we already knew that music is math.
Over the course of the study, the researchers found that catchiness was most influenced by four factors: "long and detailed musical phrases, multiple pitch changes in a song's 'hook,' male vocalists, and higher male voices making a noticeable vocal effort."
Of course, none of this accounts for why "Who Let the Dogs Out?" is still stuck in our heads over a decade later.