Axis Of Awesome: Four Chord Song
https://www.youtube.com/watch?v=oOlDewpCfZQ Why Do Songs Get Stuck in Our Heads?
http://www.sciencefriday.com/articles/why-do-songs-get-stuck-in-our-heads/ "The phenomenon is quite common. For instance, a study from the Proceedings of the 10th International Conference on Music Perception and Cognition found that more than 91 percent of people reported having an earworm at least once a week, while about a quarter had them more than once a day."
http://science.howstuffworks.com/life/inside-the-mind/human-brain/songs-stuck-in-head1.htm "James Kellaris, a marketing professor at the University of Cincinnati College of Business Administration, has done research on earworms and brain itch, and he's found that as many as 99 percent of us have fallen prey to them at one time or another..."
Want to block earworms from conscious awareness?
http://www.tandfonline.com/doi/abs/10.1080/17470218.2015.1034142?journalCode=pqje20 "Three experiments examine the role of articulatory motor planning in experiencing an involuntary musical recollection (an "earworm")."