His dual-track musical interests led him to jazz-rock fusion and included a professional performance in his later high school years with the Pittsburgh alto sax player Eric Kloss.

O'Riley is the former host of the weekly National Public Radio program From the Top, on which young musicians are heard and interviewed.

O'Riley first began performing Radiohead songs as a time-filler during a break in the program, to supplement preludes and miniatures by composers such as Debussy and Rachmaninoff.

When listeners were apprised of the title and provenance of the pieces, emails came into the show asking "Who is this Mr. Head and where can I find more of his beautiful music?"

O'Riley describes himself as an obsessed Radiohead fan in interviews, and says he was attracted to the multilayered nature of the band's music, leading him to listen to and transcribe lesser known album tracks, live bootleg recordings of performances, b-sides, and even songs never officially released, as well as some of their hit singles.

When asked to explain his unusual choice of material for a classical pianist, O'Riley has often quoted Duke Ellington's statement that "there are two kinds of music.