From the NPR Exclusive on the video:
"Head Full Of Doubt/Road Full Of Promise" was written about the temporary nature of our buildings and our mentality," says Scott Avett. "Accepting the temporary state we may be in. (Artist) Jason (Ryan Mitcham) with his landscape paintings, and some that I'd seen that he'd animated, dealt with the temporary nature of the world around us."
Rather than make a bunch of different paintings for the animation, Mitcham gradually altered a single painting 26-hundred times. Ten alterations to the painting equaled one second of film.