Why do dreadful songs haunt us and never leave our head? That's how the show begins and it's a theme that recurs throughout.

But there's more to the show than just a witty investigation of this familiar topic.

Compelling narratives - mixed with engaging back and forths between Radio Lab's soul mates and cohosts, Jad Abumrad and Robert Krulwich - take us miles beyond the "damn, this is annoying" factor associated with songs and melodies that linger like bad house guests.

Listeners will hear why melodies (good, really bad and really good) stay in our head - but also, how they come into the composer's head to begin with - Tony Hatch's "Downtown," for example, made famous by Petula Clark.

The shows hosts and guests also investigate why American Country Music is just as popular - maybe even more popular - in Asia, Africa and other places where English is not spoken. There's even an accordion story with a happy ending.

Typical of many Radio Lab topics, delivery and sound-craft, this edition is funny, clever and endlessly inventive. It's also fascinating. You'll take away some PhD level medical, psychological, neurological and musicology mega data you previously thought only the genius next door could understand.

"Radio Lab, Show 405: Pop Music" is a credible candidate for your midday schedule, post ATC and for weekend airings. The driving pace of audio probably places it later, rather than earlier in the day.

This particular program, like many earlier Radio Lab shows, lives as much as a significant informative and entertaining opportunity for listeners as it is for us who want to make memorable and compelling radio.