Lt. Col. David Grossman (U.S. Army Ret.), an expert on the psychology of killing, has written On Killing: The Psychological Cost of Learning to Kill in War and Society. He also teaches psychology at Arkansas State University, directs the Killology Research Group in Jonesboro, Arkansas, and has coined the term "killology" for a new interdisciplinary field: the study of the methods and psychological effects of training army recruits to circumvent their natural inhibitions to killing fellow human beings.  Grossman has published extensively and appeared on numerous news programs to discuss his views about the role video games and media play in the increase of violence.