Two Flew Over the Cuckoo’s Nest

Can a married couple like Randy and Evi Quaid go insane together?

Randy and Evi Quaid

Actor Randy Quaid and his wife were arrested in Canada on Wednesday. During their Friday arraignment, Quaid held up a sign indicating that the couple is seeking asylum from a group of assassins called the “star whackers,” whom they believe responsible for the deaths of Heath Ledger and David Carradine. Previously, Randy Quaid was expelled from the stage actors’ union for abusing fellow performers, and Evi Quaid suspected other actors of plotting to kill her. Is insanity contagious? Can a married couple go crazy together?

Yes. People suffering from schizophrenia, delusional disorder, or other psychotic disorders sometimes pass their symptoms along to those close to them. The medical literature on shared psychotic disorder consists almost exclusively of anecdotal cases with virtually no statistical data, but there are some patterns. Married couples and siblings are most likely to share psychoses, with sister pairs being more common than brother pairs. Ninety-five percent of cases occur within a nuclear family. The person with the root disorder, who usually experiences more severe symptoms, is often emotionally or financially dominant. The pair frequently lives in geographic, linguistic, or social isolation.

Shared psychotic disorder was first identified in France in 1860 by Jules Baillarger. (The prolific Baillarger also claimed credit for the first diagnosis of folie à double forme, or bipolar disorder, but that honor is in dispute.) It has been known at various times as communicated insanity, contagious insanity, and folie à deux (“madness of two”). It comes in several varieties. The most widely reported is folie imposée, when an affected person passes his symptoms to someone who has never shown signs of psychological problems. The recipient’s condition usually improves without medication when the pair is separated. If it doesn’t, the case is diagnosed as folie communiquée. Less common is folie simultanée, where two previously healthy individuals simultaneously develop symptoms. Not all doctors consider this a true shared psychotic disorder, since it lacks the classic dominant-subservient relationship component, and it’s impossible to tell whether the two patients would have developed symptoms on their own.

Like other contagious diseases, psychosis can become something of a mini-epidemic. There have been reported cases of folie à trois, folie à quatre, and even folie à famille, in which one person—almost always the father—drives his entire nuclear family to mental instability.

Criminal defense lawyers are particularly interested in shared psychotic disorder, because it provides a basis for the prized defense of temporary insanity. In 2001, for example, three South Carolina sisters managed to beat burglary and assault charges by arguing that the diagnosed schizophrenic member of the family infected the other two after they all moved in together. They spent the three days before the burglary praying continuously without sleep, and believed that God intended them to live in the house they invaded. When they were arrested, the police made the mistake of putting them in the same cell. After they assaulted an officer, it took 15 guards to get them back under control. However, when separated, two of the three sisters stopped having delusions.

There can be a very fine line between shared psychotic disorder and membership in a cult, in which an isolated set of acolytes may be said to share the psychoses of their leader. The latter is not a legal defense.

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