system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What is happening in your brain when a song "gets stuck" in your head?
gpt
IIRC this is due to the Zeignark effect. It basically means our mind seems to think of unfinished things very often in an attempt to complete it and in this case the unfinished thing  is the song.  

Try completing the song the next time its stuck in your head.