I Miss My Brain Sometimes

The weirdest thing...
Sometimes when I'm lost in my mind, I get to a point where I'm traveling through the tunnels and have to stop. I stop at a door, some part of my brain I can't get to anymore because it's locked and I don't have the key. It's a small piece of my former self I can't access no matter how hard I try. What's behind there? Stuff I forgot, things I can't remember? I visit my mind like this every couple of days in the hopes that one day the door will open. Maybe if I knock loud enough, it will hear me and let me in.