Our brains are inextricably linked with our musicality, whether it's intentionally exercising them to learn a new song, or letting teenage brains exercise themselves while the music sinks in!
I'll often mention (meaning: repeat ad nauseum) to ukulele players that 1. learning a skill or a song will build new neural pathways, and 2. playing a song you've learned by memory incorporates using a different part of your brain than playing it while reading the music/chord/lyric sheet. Below are a couple of diagrams that give simple visual representations of the complex processes in place (just so you know I'm not making it up!).
It is also worth noting that there are two sides (no pun intended) to the immense power of your brain - committed practice will form a path to achieve whatever it is you've practiced, so it's best to start out at a slower tempo...because if you repeat that same mistake over and over and over and over during practice, that will also be part of the outcome!
And what's happening when we hear a song from our past and we're transported to another time, place and emotional state? Here's a link to an article from online magazine Slate about why we still love the music we heard as teenagers because of the foundations our brain laid down at the time.