MIAMI — Whatever happened in Havana, where several U.S. diplomats became ill after hearing strange sounds, changed the brain structure of those affected, according to a new study published on Tuesday.
Scientists at the University of Pennsylvania Perelman School of Medicine analyzed magnetic resonance imaging scans of 40 people — 23 men and 17 women — who were exposed to sounds or vibrations while they were in the Cuban capital. When compared with images from two control groups, the researchers found “significant differences” between the groups in the volume of white and gray matter, in the cerebellum and the “functional connectivity in the auditory and visuospatial subnetworks.”
The first incidents in Havana were reported at the end of 2016 and the most recent in May of last year. The U.S. State Department confirmed that so far 26 diplomats and family members had been affected by what they considered attacks against their personnel. The study includes personnel who could have been exposed to an alleged “directional source” of energy, officials and scientists have speculated following the descriptions given by the patients.
The changes found in the new study of the Cuba patients, the most detailed so far, are consistent with some of the symptoms they have experienced, such as dizziness, balance problems and a decrease in some cognitive abilities.
But the researchers could not connect the observed changes to specific diagnoses, such as a mild brain traumatic injury or concussion, a suggestion made earlier in a previous article that published partial data of 21 patients, also authored by the UPenn team.
Scientists at the University of Miami, who first assessed the affected officials, had also questioned the concussion theory. Instead, the UM team said they found that the patients had a unique pattern of balance and cognitive dysfunctions. They also presented damages to the vestibular system of the inner ear, which is responsible for sensing the position of the body.
After more than two years and investigations by the FBI, the State Department and other agencies, the incidents in Havana, initially known as “sonic attacks,” remain a mystery.
The State Department has said that it is still not known who or what caused them. But the incidents created a diplomatic crisis between Washington and Havana. The United States withdrew almost all of its embassy staff and suspended visa processing in Havana.
Canada also took similar measures at its embassy in Cuba earlier this year, after confirming 14 cases of diplomats and family members affected with symptoms similar to those of the Americans.
Scientists investigating the case have speculated there may be an unknown weapon that could direct energy — microwaves and electromagnetic energy are the main suspects — and cause those effects.
That idea has been received with skepticism among many scientists. The Cuban government has repeatedly denied that attacks had occurred against U.S. officials on the island, and even that the incidents had taken place.
Other experts and media outlets have speculated that the symptoms felt by the diplomats were the result of functional disorders or collective hysteria, all grounded in psychological mechanisms. But the article published on Tuesday reinforces what doctors with direct access to the patients have said: that some of the symptoms presented by diplomats cannot be easily faked.
At the same time, the sample used by the study is small, and the images were taken at different intervals after the incidents occurred, so the authors conclude that the clinical importance of the differences found in the brain of the patients “is uncertain and may require further study.”
