After earning a B.A. in economics and a B.S. in accounting at the State University of New York at Binghamton, Gershenhorn earned graduate degrees in history, an M.A. from North Carolina Central University and a Ph.D. from the University of North Carolina at Chapel Hill. His research and teaching interests are American history, African American history, American Intellectual history, and North Carolina history. In 2004, he published Melville J. Herskovits and the Racial Politics of Knowledge (Lincoln: University of Nebraska Press). He has also published several journal articles on North Carolina history and African American history.
He has taught at North Carolina Central University for over fifteen years. In 2007, he received the North Carolina Central University Award for Teaching Excellence. He has also taught at Central Carolina Community College, North Carolina A & T State University, St. Augustine's College, and North Carolina State University.
In Spring 2009, he was a Scholar-in-Residence at the Schomburg Center for Research in Black Culture in New York City, where he conducted research on black scholars and the development of African Studies Programs during the early Cold War era.
He appears as an on-screen contributor and served as a consultant for the documentary film, "Herskovits at the Heart Of Blackness" (Vital Pictures, 2009)