Does mass hysteria explain the “sonic attacks” on US diplomats in Cuba?

There are more plausible explanations for the strange events in Havana in 2016 than the development of a new hi-tech communist weapon.

Sign Up

Get the New Statesman\'s Morning Call email.

Remember the time Cuba apparently developed a mysterious hi-tech superweapon and used it to attack US diplomatic personnel, before we all moved on and stopped thinking about it?

It happened only a few years ago. I had almost forgotten the whole bizarre episode, but last week a US State Department document was declassified that provided a reminder of – though not a definitive answer to – the mystery.

In late 2016, some US diplomats in Havana began to hear loud, high-pitched noises at night in their homes or hotel rooms. They described a laser-like “beam” of sound, seemingly aimed at them from outside with no obvious source. They soon reported being struck by a range of concussion-like symptoms including dizziness, nausea, tinnitus and insomnia, and even cognitive problems such as memory loss. Rumours began to spread of a “sonic attack” by a new, advanced energy weapon, an unprecedented way to direct sound towards individuals at a frequency that would cause them physical harm.

By mid-2017, Donald Trump had slashed the number of staff at the US embassy in Havana and – contrary to the advice of his own State Department, which still considered the symptoms unexplained – explicitly blamed Cuba for the injuries suffered by the diplomats. Last week’s declassified review provided a strong critique of how Trump’s State Department dealt with the situation: for example, in failing to assign anyone ultimate responsibility to investigate what happened.

It’s hardly a surprise that the Trump administration fumbled the handling of a delicate diplomatic matter. But there is an important scientific lesson we can draw from how some peer-reviewed papers helped prolong the story by seemingly providing backing for the sonic attack theory on the basis of little to no evidence.

In a 2018 paper in the Journal of the American Medical Association, a team of neurologists described giving 21 of the affected diplomats a range of tests, including of their balance, mood, vision and cognitive skills. It found “a constellation of neurological signs and symptoms commonly seen following mild traumatic brain injury” – concussion, but without a hit to the head. The symptoms came “after exposure to an unknown energy source”, which was “directional” and “non-natural”. There it was: a scientific study agreed that the diplomats had been attacked. The paper was cited in an “alert” by the embassy.

[see also: Why should Joe Biden be different when US foreign policy has always been dictated by self-interest?]

The paper wasn't received well in the scientific community. A flurry of critical letters appeared, arguing that it hadn’t come close to proving the case for the sonic attack. For one thing, the neurologists misinterpreted the results of the cognitive tests – they’d given such a large number of tests and adopted such a liberal threshold for an impairment that they were statistically bound to find something “amiss” in almost every patient.

Then came an MRI-scanning study in 2019 that claimed to have found “significant differences” in the brains of the Havana diplomats. But those differences were compared to a set of control subjects who had likely never set foot in Cuba. The results were also a mess: apparently the sonic attacks – or, as the paper rather mysteriously called them, “directional phenomena” – had caused some parts of the diplomats’ brains to shrink, but some to expand; some aspects of the subjects' brain connectivity had got worse, but some aspects had got better.

But the patients had reported concussion-like symptoms. Even if the objective evidence for symptoms is weak, what caused subjective reports of them in the first place? The episode might be explained by one of medicine’s oddest phenomena: mass psychogenic illness. Known in the past as “mass hysteria”, it occurs now and again: for instance, citizens of various cities have reported being affected by “The Hum”, a strange, persistent noise that they blame for causing symptoms such as dizziness and insomnia. Does that – no pun intended – sound familiar?

[see also: Simon’s strange pains had left us baffled. Time for the surgical sieve – a tool for facing the unknown]

People suffering from mass psychogenic illness aren’t making it up. The very real symptoms are often caused by high-stress situations (for example, an American diplomat being posted to a country with which the US has a notoriously difficult relationship) and by seeing other people who are affected (it’s noteworthy that there was an uptick in symptom reports after embassy officials informed their staff of the attacks). 

What about that high-pitched sound? It’s not 100 per cent certain, but the sound in one recording was found to be virtually identical to… the call of the Indies short-tailed cricket. Perhaps that’s a more plausible explanation than a dastardly new hi-tech communist weapon.

One critique of the sonic attack theory noted the power of doctors to turn a set of non-specific symptoms into clear diagnoses. To that I’d add the power of low-quality scientific studies to transform a bunch of sparse, uncertain data into a very specific story – in this case about the effects of an “unknown energy source”. We may never know exactly what happened to the diplomats in Havana, but it’s yet another instance of how putting too much faith in scientific papers – rather than science itself – can leave us more, not less, confused than before.

Stuart Ritchie is a psychologist at King’s College London and the author of Science Fictions: How Fraud, Bias, Negligence and Hype Undermine the Search for Truth

Free trial CSS