The Joker's main characteristic is his apparent insanity, although he is not described as having any particular psychological disorder. Like a psychopath, he lacks empathy, a conscience, and concern over right and wrong. In Arkham Asylum: A Serious House on Serious Earth, the Joker is described as capable of processing outside sensory information only by adapting to it. This enables him to create a new personality every day (depending on what would benefit him).