Following his evaluation of Ted Bundy, Dr. Carlisle used his findings to understand how sadistic serial killers can present themselves socially as normal. This understanding was built on three psychological processes: fantasy, dissociation, and compartmentalization.

Psychology Today describes the fantasy process as imagining scenarios that would be entertaining or comforting. According to Carlisle, Bundy had been an awkward outsider in his childhood, which was a major factor in his use of sadistic fantasies and a false persona to self-soothe. Reading true crime and porn fueled his fantasies of rape and murder, which gradually intensified as they played out in his mind over and over as the years went by.

Dissociation, or detaching oneself from unpleasant feelings or memories, and compartmentalization, or placing one’s different thoughts and actions into separate categories, also likely played roles in Bundy’s ability to create a charming persona despite his awkward childhood and gruesome crimes. “Compartmentalization is a process that all of us can engage in to one degree or another,” Carlisle told Psychology Today. “It’s a complex state of mind on a continuum that can vary from a healthy level, such as with an actor who rehearses a script so intently that when portraying that role on stage or in a film he has a deep sense of being that person. At the other end of the continuum is a very destructive process that can result in violence.”