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The Power of Premonitions

What are “predictive processing” and the “nocebo effect”?

This post is a review of The Premonitions Bureau: A True Account of Death Foretold by Sam Knight. Penguin Press. 256 pp. $28.

On October 21, 1966, thousands of tons of liquified waste from a coal mine collapsed on the Welsh village of Aberfan, destroying buildings and killing 144 people. When John Barker, a psychiatrist at Shelton Hospital, a mental institution outside Shrewsbury, in England, learned that several people had warned of an impending disaster, he decided to conduct an experiment: invite English men and women to send their forebodings to London’s Evening Standard and investigate the people who contributed them.

In January 1967 the Standard launched what it called a Premonitions Bureau. Fifteen months later, 723 predictions had been collected. According to Peter Fairly, science editor of the newspaper, 18 of the warnings had come true, a rate of about 3 percent, very low but not nothing. And 12 of the 18 apparent successes came from two people, Miss Lorna Middleton, a music teacher, and Alan Hencher, a telephone operator.

In The Premonitions Bureau, Sam Knight, a staff writer at The New York Times, provides a wide-ranging account of our enduring fascination with visions and forebodings. “Premonitions are impossible,” Knight writes, but many of us believe they have had them.

Knight indicates that choosing which premonitions, if any, should affect decisions we make in our lives may well be impossible. An exchange between a reader and Dr. Barker may well reflect Knight’s uncertainty about the phenomenon. “To invent a weird terminology for a series of haphazard guesses,” the anonymous reader declared, “and to attempt, unreasonably, to reason with undefined and undefinable data is undignified.” Apparently unruffled, Barker replied: “Existing scientific theories must be transformed or disregarded if they cannot explain all the facts. Although unpalatable to many, this attitude is clearly essential to all scientific progress.”

Acting on premonitions to prevent disasters, moreover, results in an unintended, ironic consequence: non-events undermine the credibility of seers.

That said, Knight enlarges and enriches our understanding of peering into the future. In the mid-nineteenth century, he reveals, Hermann von Helmholtz suggested that to cope with the avalanche of information bombarding us, we often make “unconscious inferences” about what we expect to see. Neuroscientists now call this phenomenon “predictive processing.” Getting a leg up “in the predictive world,” according to Phil Corlett, a professor of psychiatry at Yale, is “really, really advantageous” and a more predictable existence is less frightening.

In 1942, Walter Cannon, the head of physiology at Harvard Medical School, used the term “voodoo death” to describe the biological phenomenon of dying of fear, a response of “primitive people” to a prophesied end. Barker believed the concept could exist in Western societies as well. And, indeed, in the 1960s, Walter Kennedy, a British physician and public health expert, emphasized the influence of the non-specific negative expectations of patients by coining the term “nocebo [I will harm] effect,” the opposite of placebo (I will please). In 2014, the Swedish Board of Health and Welfare officially recognized “resignation syndrome” as a diagnosis.

The impact of the nocebo effect, Knight indicates, is often evident in drug trials. Warned about possible side effects, volunteers frequently develop them, even when they are given sugar pills. In 2005, 120 men being treated for enlargement of the prostate gland were given the drug finasteride. After a year, 44% of the men who were told the drug could improve sexual dysfunction complained of erectile problems and decreased libido, compared to 15% who were not.

And the nocebo effect can have a social dimension. When the manufacturer of Eltroxin, a thyroid replacement drug, moved its plant from Canada to Germany, changed the shape and color of the pills (but not the ingredients), and the media reported it was cheaper to make, reports of side effects rose by a factor of 2,000.

John Barker, it’s worth noting, wrote a book entitled Scared To Death. And on the morning before a vessel burst in his brain, Miss Middleton, who had already warned him of a dream “that may mean a death,” woke up with a choking sensation and called out for help.

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More from Glenn C. Altschuler Ph.D.
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