Mondo bizarro

Researchers identify similarities between dreams and psychotic thoughts

Dreams and psychotic ruminations have certain strange features in common, and psychiatrists have now measured the degree of similarity.

Both dreams and waking psychotic moments share cognitive bizarreness — a well-defined term in psychology. It consists of impossible plots, characters and actions: flying over Elvis’ first concert or conversing with Fido the dog. It also includes discontinuity or uncertainty in time and place: stepping outside your house, which is really your aunt’s house, and onto Mars, the day before.

“We are not talking about hallucinations,” says Silvio Scarone of the University of Milan in Italy, “but rather the organization of thinking.” When awake, normal people don’t have bizarre fantasies, he says. But when asleep, their dreams are as bizarre as a schizophrenia patient’s waking fantasies.

To examine these fantasies, Scarone and his team instructed normal people and schizophrenia patients to tell a fantastic tale about a given image. The stories were systematically scored according to how bizarre the tales were. Normal people’s plotlines contained few signs of bizarreness, whereas the plotlines of schizophrenia patients contained as many bizarre, illogical jumps as dreams do. The researchers also scored people’s descriptions of their dreams. Normal people and those with schizophrenia showed similar levels of cognitive bizarreness in their dreams, the researchers report in the May issue of Schizophrenia Bulletin.

By understanding the organization of schizophrenic thought, psychiatrists might be better able to communicate with their patients, Scarone says.

Bizarreness appears to arise when sensory information from the outside world is blocked, and when thoughts are heavily influenced by an excess of emotion, says Harvard Medical School psychiatrist J. Allan Hobson, another researcher on the study. A predominance of the inner world characterizes a variety of mental illnesses. Likewise, the dreaming mind cuts off outside stimuli. “It’s not just a dull waking state,” Hobson says. “It’s an entirely different state of consciousness.”

But bizarreness isn’t the only thing that lurks beneath madness. Other elements of psychotic episodes include delusions of grandeur and paranoia. Dreams, however, generally don’t exhibit these qualities. Normal dreamers rarely imagine being chased by the KGB, Scarone says. This difference may indicate that the two erratic modes of logic, bizarreness and delusion, occur by separate mechanisms.

Still other researchers think the gap between psychosis and dreaming is wider. G. William Domhoff of the University of California, Santa Cruz expresses skepticism about any connection at all. “Dreams are far more coherent, far more consistent over time and far more continuous with waking conceptions and concerns,” he says.

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