Gaslighting is a form of psychological abuse in which false information is presented to the victim with the intent of making them doubt their own memory and perception. It may simply be the denial by an abuser that previous abusive incidents ever occurred, or it could be the staging of bizarre events by the abuser with the intention of disorienting the victim. Gaslighting had a colloquial origin explained below, but the term has also been used in clinical and research literature.
The term derives from the 1938 stage play Gas Light (originally known as Angel Street in the United States), and the 1940 and 1944 film adaptions. The plot concerns a husband who attempts to drive his wife to insanity by manipulating small elements of their environment, and insisting that she is mistaken or misremembering when she points out these changes. The title stems from the husband's subtle dimming of the house's gas lights, which she accurately notices and which the husband insists she's imagining.
Gaslighting has been used colloquially since at least the late 1970s to describe efforts to manipulate someone's sense of reality. In a 1980 book on child sex abuse, Florence Rush summarized George Cukor's 1944 film version of Gas Light, and writes, "even today the word [gaslight] is used to describe an attempt to destroy another's perception of reality." 
Gaslighting and Introjection
In an influential article "Some Clinical Consequences of Introjection: Gaslighting", the authors argue that gaslighting involves the projection and introjection of psychic conflicts from the perpetrator to the victim: 'this imposition is based on a very special kind of "transfer"...of painful and potentially painful mental conflicts'.
They explore a variety of reasons why the victims may have 'a tendency to incorporate and assimilate what others externalize and project onto them', and conclude that gaslighting can be 'a very complex, highly structured configuration which encompasses contributions from many elements of the psychic apparatus'.
Clinical and popular examples
Psychologist Martha Stout states that sociopaths frequently use gaslighting tactics. Sociopaths consistently transgress social mores, break laws, and exploit others, but are also typically charming and convincing liars who consistently deny wrongdoing. Thus, some who have been victimized by sociopaths may doubt their perceptions.
Psychologists Gass and Nichols use the term gaslighting to describe a dynamic observed in some cases of marital infidelity:
- "Male therapists may contribute to the women's distress through mislabeling the women's reactions. [...] The gaslighting behaviors of the husband provide a recipe for the so-called 'nervous breakdown' for some women [and] suicide in some of the worst situations."
Examples from media
In the Wes Anderson film The Darjeeling Limited the character Peter asks his brother Jack, "Could she be gaslighting you?" after he found that Jack's ex-girlfriend had stashed a bottle of her perfume in his luggage.
Lee Majors, playing the character of Steve Austin in the series The Six Million Dollar Man, uses the term early in the episode "The Seven Million Dollar Man" (which first aired in November 1974) when he complains that his boss, physician, and a nurse are conspiring to convince him that something he's witnessed did not, in fact, transpire as he believes it did.
In the M*A*S*H Season 3 episode Love and Marriage (M*A*S*H), a Korean medic is caught with a forged pass. When Colonel Blake confronts Hawkeye and Trapper about it, saying that he saw the pass at the poker game they played the night before, Hawkeye and Trapper reply in unison, "What poker game?" Colonel Blake then asks Radar if they played a poker game last night, to which Radar responds, "If you say so, sir." Colonel Blake then says, "Oh, I get it. You're trying to gaslight me, right?"
The term has been used extensively over the past two years on the Soap Opera The Young and The Restless to describe the actions of Adam Newman (Victor Newman's son) by various members of the cast. Adam is constantly accused of gaslighting Ashley Abbott about the baby Adam caused her to miscarry.
More recently it was displayed in the mid-season finale of TV's "Gossip Girl" (in an episode appropriately titled "Gaslit") in which a character manipulates the main character, Serena VanDerwoodsen, into believing that she has returned to a life of drug abuse.
With respect to women in particular, Hilda Nelson argued that 'in gaslighting cases...ability to resist depends on her ability to trust her own judgements '. Establishing "counterstories" to that of the gaslighter may help the victim re-acquire or even for the first time ' acquire ordinary levels of free agency'.
- Gass, Gertrude Zemon and William C. Nichols. 1988. Gaslighting: A marital syndrome. Journal of Contemporary Family Therapy, 10(1), 3-16.
- Jacobson, Neil S. & John Mordechai Gottman. 1998. When men batter women: new insights into ending abusive relationships. NY: Simon & Schuster. ISBN 0684814471, pp. 129-132.
- Rush, Florence (1980). The best kept secret: sexual abuse of children. Englewood Cliffs, NJ: Prentice-Hall. p. 81. ISBN 0-13-074781-5.
- Victor Calef and Edward M. Weinshel, in Edward M. Weinshel/Robert S. Wallerstein, Commitment and Compassion in Psychoanalysis (Routledge 2003) p. 83
- Calef/Weinshel, p. 83 and p. 90
- Stout, Martha. 2005. The sociopath next door: the ruthless versus the rest of us. NY: Random House, ISBN 9780767915816, pp. 94-95
- Bishop, Victor George Witness To Evil Pages 19,146 & 147, Nash Pub., 1972 Accessed via Google Books August 13, 2009
- Hilda L. Nelson, Damaged Identities, Narrative Repair (Cornell 2001) p. 31
- Nelson, p. 32