US diplomats’ brain injuries may be from covert microwave attack, experts say

In late 2016, US diplomats in Cuba began reporting bizarre and alarming episodes in their homes and hotel rooms. They spoke of irritating or piercing noises—buzzes, squeals, or clicks—that seemed to come from a particular direction but weren’t always dampened when they clasped their hands to their ears. Some described feeling pressure and vibrations, too.

With the disturbances came a constellation of debilitating symptoms: dizziness, nausea, headaches, balance problems, ringing in their ears, visual disturbances, nosebleeds, difficulty concentrating and recalling words, hearing loss, and speech problems.

Since the first 2016 reports, the mysterious episodes seemed to afflict more than 50 US diplomats and their families; more than 40 in Havana and at least a dozen more at the US Consulate in Guangzhou, China. Some CIA officers working in Russia have also reported similar cases.

Some victims have recovered; others suffer chronic symptoms and are still unable to work. Exhaustive medical studies on some of the Cuba diplomats determined the diplomats had sustained “injury to widespread brain networks.” The doctors who examined the victims were so baffled they began referring to their condition as the “immaculate concussion”—traumatic brain injuries without any obvious blows to the head.

Under attack

Almost from the start, the US State Department considered the episodes targeted "health attacks," sparking wild speculation of cloak-and-dagger operations with high-tech clandestine weaponry. Cuba and China quickly and adamantly denied any knowledge of or involvement with the episodes. Officials in the US eyed Russia—which remains a prime suspect.

Scientists and journalists quickly began batting around possibilities of a sonic weapon, malfunctioning surveillance equipment, or a dastardly device that beamed microwave radiation at people.

Others were skeptical that any attack took place—or that people were even injured. Two neurologists—who did not have access to the diplomats or all their medical data—raised doubts about some of the clinical methods used to conclude they suffered brain injuries. The neurologists suggested evaluating doctors merely documented cognitive deviations in the normal range, which the evaluating doctors disputed by citing data withheld due to privacy and security concerns.

Cuban scientists—who also did not evaluate the diplomats—suggested the episodes were due to stress and a mass psychogenic illness (MPI), essentially a collective delusion, which the evaluating doctors also disputed. Biologists in the US and UK, meanwhile, suggested the noisy disturbances the diplomats reported were simply the clamor of crickets in search of mates.

While each possibility may seem as farfetched as the last, the most disquieting one may actually be the closest to the truth.

According to a new report by a committee of scientific experts assembled by the National Academies of Sciences, Engineering, and Medicine, the “most plausible mechanism” that explains the diplomats’ experiences and symptoms is directed pulsed radiofrequency energy. In other words, a dastardly device that beams bursts of microwave radiation at people’s heads.

New analysis

The expert committee, which was assembled at the request of the US State Department, was not tasked with considering how the diplomats may have been exposed to such a device. But the implications of the committee’s conclusion were abundantly clear.

“The mere consideration of such a scenario raises grave concerns about a world with disinhibited malevolent actors and new tools for causing harm to others, as if the US government does not have its hands full already with naturally occurring threats,” committee chair and Stanford researcher David Relman wrote in the report’s preface.

But Relman and the other experts on the 19-member committee were at a loss to find any other, less worrisome explanation that fit. And they evaluated many. The committee—titled the Standing Committee to Advise the Department of State on Unexplained Health Effects on US Government Employees and Their Families at Overseas Embassies—included researchers with expertise spanning neurology, psychiatry, epidemiology, neuroaudiology, electromagnetic engineering, exposure science, and radiology. It met several times between December 2019 and May 2020, and it invited other experts to discuss specific topics.

Tasked with assessing clinical features and plausible mechanisms of the diplomats’ experiences and injuries, the committee ruled out chemical exposures—specifically insecticides used around Havana—as a likely explanation for what happened. The experts also found that infectious diseases, such as Zika, were an unlikely explanation.

Similarly, the committee was unconvinced by the Cuban scientists’ suggestion that psychological and/or social factors were at the root of the situation. Though the committee noted that it lacked case-level data to fully evaluate this hypothesis, it expressed skepticism that delusional disorders could explain some of the acute and chronic symptoms of the diplomats’ experiences. On the other hand, psychological and/or social factors can easily explain some of the nonspecific chronic symptoms, such as dizziness and fatigue, that some diplomats reported. As such, the committee concluded that those factors may contribute to some of the cases.

But of all the possibilities considered by the committee, the one that fit best was directed, pulsed radiofrequency energy. The committee, which looked through published scientific reports, found that pulsed RF energy could explain the sounds and sensations as well as the acute and chronic symptoms reported by the diplomats.

RF effects

In their assessment, the experts looked at all the biological effects of RF exposures, which are defined as 30KHz-300GHz, including microwave radiation at 300MHz to 300GHz. In recent years, studies have suggested that low-level RF exposures that don’t generate heat—non-thermal exposures—may be able to disrupt the activity at cell membranes as well as cause oxidative stress and even cell death.

But the data that firmly linked the experiences of the diplomats to RF exposures came from studies looking at pulsed RF exposures. “There was significant research in Russia/USSR into the effects of pulsed, rather than continuous wave (CW) RF exposures because the reactions to pulsed and CW RF energy at equal time-averaged intensities yielded substantially different results,” the report notes.

In a review of Russian-language studies, researchers found that “pulsing may be an important (or even the most important) factor that determines the biological effects of low-intensity RF emissions.” The report notes that some of the studies involved exposing military personnel in Eurasian communist countries to non-thermal microwave radiation. Afterward, the military personnel reportedly experienced eerily similar symptoms to those reported by the diplomats. That is, they experienced headache, fatigue, dizziness, irritability, sleeplessness, depression, anxiety, forgetfulness, and lack of concentration, as well as internal sound perception from frequencies between 2.05 to 2.50GHz. Other studies have since backed up the finding that pulsed RF can have wide-ranging effects on the nervous systems of animals and humans, including negative effects on cognition.

RF exposure can also explain the bizarre auditory and sensory experiences reported by the diplomats, the committee noted. For this, the experts turned to data on the “Frey effect,” which was identified by American researcher Alan Frey in 1961. Frey found that pulsed microwaves can essentially be perceived as sound by humans, even those who are deaf. In summarizing some of Frey’s findings, the committee’s report noted:

The areas near the ear were most sensitive to these RF exposures; modulating the RF energy could produce a variety of effects including the perception of “buffeting of the head” or pressure on the face/head without dizziness or nausea, a “pins and needles sensation,” and a sound described as a “buzz, clicking, hiss, or knocking” within the head for RF frequencies between 0.4-3 GHz, depending on pulse width, pulse-repetition frequency (PRF), and peak power density… Frey reported these symptoms with an RF source transmitting at 1.3 GHz (which provides the greatest absorption depth into cortical tissue) with a PRF of 244 Hz, 6 μs pulse width, peak power density of 267 mW/cm2, and average power density of 0.4 mW/cm2. Others have demonstrated that GHz range, pulsed RF energy (~14μs pulse width) interacting with common materials can produce external sounds that are audible to nearby humans.

Last, the committee also noted that the pulsed RF explanation also fit with the common report from diplomats that the episodes they experienced were only in “specific physical locations near windows or as originating or emanating from a particular direction.”

“Quite concerning”

The committee was careful to avoid saying its report was conclusive. The experts noted significant limitations to the data and their access to it. For one thing, much of the data provided to the committee was aggregated data on the diplomats’ cases, not data on each case individually. In addition, some of the data was collected months after the diplomats fell ill, making it difficult to assess health effects.

Still, the data fitting pulsed RF exposures is disturbing—and perhaps not as outlandish as it first seemed. As Ars has noted before, the discovery of the Frey effect is well-known to have launched decades of research into microwave weapons and devices. The line of research was certainly pursued by Russian, Soviet, and US researchers. Research funded by the US Navy even led to the development of a crowd-control weapon called MEDUSA (Mob Excess Deterrent Using Silent Audio), which uses low-energy microwave pulses to produce strong, uncomfortable sounds in people’s heads. There’s open speculation that Russia has developed its own microwave-based weapon and has begun deploying it.

In a press statement, Relman touched on the disturbing nature of the committee’s findings, saying:

The committee found these cases quite concerning, in part because of the plausible role of directed, pulsed radiofrequency energy as a mechanism, but also because of the significant suffering and debility that has occurred in some of these individuals. We as a nation need to address these specific cases as well as the possibility of future cases with a concerted, coordinated, and comprehensive approach.