In the third verse Twenty One Pilots expresses the personification "sometimes quiet is violent" to understand where the mind goes when all their is to listen to is himself. It can be lonely and torturous at times when it feels forced to think about all the thoughts that people try to avoid on a daily basis.
One of the more blunt verses has the power to be straightforward but to also make the listener feel and understand how his transportation has changed him,
"I ponder of something terrifying
'Cause this time there's no sound to hide behind
I find over the course of our human existence
One thing consists of consistence
And it's that we're all battling fear
Oh dear, I don't know if we know why we're here
Please stop thinking
I liked it better when my car had sound"
Twenty One Pilots takes something so simple, that almost every adult does multiple times a day and to exaggerate the point that when left alone, in silence our own minds is what can be the most fearful part of our world. Every fear is in the mind and can be overcome by how it's perceived, but what's questioned is if the cure to all fears is an adjustment in the mind then the question is can a fear of your own mind be cured the same way.