Explainer

Do Crazy People Have Crazy Dreams?

Yes, but so do sane people.

A man dreaming

Arizona shooting suspect Jared Loughner was obsessed with the meaning of his dreams, according to a friend. Loughner recorded them in a notebook every morning and attempted to interpret them. Do mentally ill people have particularly crazy dreams?

Probably not. There are anecdotal reports that mentally ill patients have especially strange dreams, and some psychologists insist they can use dreams to identify a descent into psychosis. However, what little evidence exists on the question suggests that the dreams of the mentally ill are no weirder than anyone else’s. In 2008, a team of Italian researchers gathered dream reports from 30 schizophrenics and 30 people in good mental health. Judges scored the dreams on a “bizarreness index,” considering the number of impossible or improbable elements in each one. On average, the schizophrenics’ dreams were almost exactly as bizarre as those of the control group.

This is one of the many unsettled questions about the significance of dreams. While some psychologists believe that dreams analysis can uncover a person’s hidden anxieties and emotions, no one has been able to prove it. Most of the evidence consists of individual case reports and a scattering of studies in which patients who engage in dream interpretation report better self-awareness and personal insight, increased likelihood to stick with therapy, and a decrease in troubling, recurrent dreams. The skeptics counter that none of this proves that dreams provide a window into a person’s psyche. There are also a handful of studies in which experts accurately predict a subject’s personality traits based on dream descriptions, but these studies have serious methodological flaws. For example, the subjects might give away their traits through the way they describe their dreams.

Practitioners of dream analysis have not coalesced around a single method for their work. Today, there are at least 12 major schools of dream interpretation (PDF), which can be broken into two broad groups: Some psychologists, taking their cue from Freud and Carl Jung, think that dreams are a counterpoint to the waking mind. In dreams, they say, the mind lets loose the concerns, emotions, and desires that it cannot play out in normal life. The psychologist’s job is to decode the symbols and images in the dream. Continuity theorists, inspired by Alfred Adler and others, believe elements of a dream are usually direct representations of their real-world analogues. If a patient described fighting with his best friend in a dream, a continuity theorist might think that the patient was angry at his friend. A Freudian would try to figure out what the figure of the friend represents.

Despite the plethora of dream theories—or perhaps because of it—74 percent of clinical psychologists report using dream interpretation only occasionally or not at all. And, in most cases, it is the client, not the analyst, who initiates the dream conversation.

Many laypeople are convinced that their dreams are significant because they confuse genuine REM-sleep dreams—which are prolonged, dialogue-heavy, and usually replete with bizarre plot elements—with the hazy imagery that occupies your mind as it fades into or out of sleep. It’s important to keep these two categories separate, because mere sleep thoughts are a part of your conscious, wakeful mind. It’s not at all surprising that an assassin might envision a murder while falling asleep. But there’s no evidence that a murderer dreams of murder more often than anyone else during REM sleep.

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Explainer thanks Mark J. Blechner, author of The Dream Frontier, J. Allan Hobson of Harvard Medical School, and Antonio Zadra of the Universite de Montreal.

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