Here's something I'd love to dive deeper into:
Why do we get some songs stuck in our head?
The book “Made to Stick” analyzed it wonderfully for stories and words. But what about music?
There are some songs I haven't heard in 30 years, but I can still play them in my head on call. (example)
Yesterday afternoon I heard the song “Tonight” by Lykke Li, and this morning woke up still singing it. (Great repeating 1-bar hook with the highest note on the downbeat. Find the full album version with great orchestration.)
My old teacher Jack Perricone has some great lessons for songwriters on writing memorable melodies, but that doesn't get into why music sticks in our brain.
Books like Brain Rules analyze evolutionary reasons why our brains do the things they do. (“Brains in wild animals are 15%-30% larger than tame, domestic counterparts. The cold, hard world forced the wild animals into constant learning mode. It is the same with humans.”)
But why music?