Benson was born in 1949 in Princeton, New Jersey. While in high school, Benson became interested in contemporary art, film and theater. During his college years, he was close to composer Humphrey Evans III, dramatist Evan McHale, actor Drew Denbaum, novelist Paul Grimes, and poets Kit Robinson, Alan Bernheimer, Michael Waltuch, John Alter, and David Wilk among others. He studied writing with Susan Holahan, Peter Schjeldahl, and Ted Berrigan.

In 1976, Benson moved to San Francisco with his friend, his then partner, Carla Harryman. With Harryman and a number of other young poets including Ron Silliman, Lyn Hejinian, Barrett Watten, Kit Robinson, Tom Mandel, Alan Bernheimer, Rae Armantrout, Ted Pearson, Bob Perelman and others he was instrumental in creating Language Poetry, a new school of innovative writing that emerged in San Francisco, New York, and other places during this period. Where much language poetry is seen as emphasizing linguistic features of the literary text, Benson became widely known and admired for his forays into questions of process, especially the process of improvisation, both in composition and in performance.

Benson has a BA from Yale and an MFA from the University of California at Irvine, as well as a PhD in Psychology from the Wright Institute.