Cuba Audio Attack: U.S. Government Workers Exposed to Mystery Phenomenon Had Brain Matter Alterations, Scientists Discover

The U.S. government personnel who got "Havana syndrome" following an alleged "sonic attack" in Cuba suffered from brain matter alterations, MRI scans have revealed. Compared with unaffected, healthy individuals, the 40 workers who experienced the phenomenon were found to have key differences in their brain matter volume, as well as lower functional connectivity in the auditory and visuospatial subnetworks of the brain.

In late 2016, staff at the U.S. embassy in Cuba and their families started to report strange neurological problems. They would have trouble concentrating, suffered from dizziness and visual problems, and struggled balancing. They also reported ear pain.

These symptoms were linked to sudden and intense loud noises they had heard in their homes and hotels. The sounds ranged in frequency and length. These "attacks" continued through to 2018. While several theories have been put forward about the origin of the sounds, the mystery remains unsolved. President Donald Trump suggested Cuba was responsible, while a non peer-reviewed study released in January said the sound matched the echoing call of a Caribbean cricket.

Following the Cuba incident, workers were taken to The University of Pennsylvania's Center for Brain Injury and Repair. Here, they were evaluated and rehabilitated, with initial evaluations suggesting the symptoms they had presented with were consistent with persistent concussion syndrome. However, there was no evidence of head trauma to any of the patients.

Before their treatment began, the 40 staff members underwent MRI scans. Scientists at Penn have now analyzed these and compared them to the scans of 48 healthy individuals. Their findings, published in JAMA, show what impact the exposure had on their brains.

Ragini Verma, a professor of radiology who led the study, said the differences observed are unlike anything documented—such as traumatic brain injury or concussion.

"These findings may represent something not seen before," study co-author Douglas H. Smith said in a statement.

Researchers looked at three components of the brain—volume, functional connectivity and tissue structures. They discovered there were differences in brain matter volume, tissue properties and regions of the brain involved in hearing and seeing. "The areas implicated in the patients' brains, namely the cerebellum as well as the visuospatial and auditory networks, align with the neurological symptoms that were observed in the patients," Verma said in the statement. "These differences persisted even when people with some history of brain injury were excluded from the analysis."

The differences in tissue volume and connectivity were found to be in the part of the brain that is responsible for performing tasks like writing and walking. "The cerebellar findings in this neuroimaging study are notable, given that a number of the patients evaluated exhibited abnormalities in balance and the coordinated movement of the eyes, both of which are associated with cerebellar dysfunction in the brain," study co-author Randel Swanson explained.

Verma said more research will be needed to understand what sort of brain injury the government workers experienced. "It's hard to tell where the problem started; the brain differences observed could be an immediate effect of the brain injury, or it could a compensatory effect of the recovery process," he said, adding that conducting a retrospective study on people who experienced different levels of exposure presents major problems.

What was responsible for the symptoms is not known. In 2018, U.S. diplomats working in China started experiencing similar symptoms—and at the time Smith told CNN that he suspects microwaves may be involved. "It's almost like a concussion, but without a concussion—meaning that they look like individuals who have persistent concussion symptoms but have no history of head impact," he told the broadcaster. "Just like we have ways to prevent people from having a concussion, you could think of maybe protecting your brain from these energy sources."

US cuba embassy
The U.S. Embassy in Cuba after workers experienced the mystery illness. ADALBERTO ROQUE/AFP/Getty Images