Since 2013 Mattison and Ernest Suarez have edited “Hot Rocks: Songs and Verse,” an ongoing feature in Five Points: A Journal of Literature and Art.

[3][6] Before graduation from high school, he'd learned to play the recorder, clarinet, tenor saxophone, french horn, trombone, bass, and guitar, in addition to his ability to sing.

After listening to the band play the arrangement of "I Wish I Knew" in the style of Nina Simone, an NPR host mentioned a "growly" quality to Mattison's voice, which Trucks was able to closely duplicate on the slide guitar.

On July 17, 2013, Mattison launched a Kickstarter Project,[11] called "untitled-not-so-secret-mike-Mattison-solo-album" which successfully raised its funding goal on August 17, 2013.

In addition to recording and touring with the Tedeschi Trucks Band and Scrapomatic, Mattison and Ernest Suarez have held seminars on a literary genre they call Poetic Song Verse at various universities since 2016.

Their book, Poetic Song Verse: Blues-based Popular Music and Poetry, was published by the University Press of Mississippi in 2021.