The first brain-imaging study of US diplomats who reported suffering from mysterious ailments in Cuba appears to back up their story that something happened—but what that might be remains unclear. Researchers say the 40 diplomats studied have clear differences in their brains compared to a control group, they report in the Journal of the American Medical Association. The University of Pennsylvania researchers cannot say what caused these differences, only that they exist. “The main thing we can do with brain imaging is ask whether something happened to the brain,” lead author Ragini Verma tells the New York Times. “And the answer we found is that yes, it did.” The diplomats have less white matter, along with differences in the regions of the brain that control balance, vision, and hearing.
"It is pretty strange. It's a true medical mystery," says Verma. However, the AP quotes an outside neurologist who says the study does not confirm that any brain injury occurred or that the differences in the diplomats' brains compared to the control group can be attributed to anything that happened in Cuba. As CNN notes, the scientists did not have MRIs of the diplomats' brains before their stays in Cuba, as a matter of comparison. The US eventually pulled all of its diplomats from the country when one after another began reporting symptoms. They ailments first surfaced in 2016, but their cause remains unexplained to this day. The US has accused Cuba of staging some kind of an attack, but Cuba denies it. Theories floated have included spytech, a "mass psychogenic" event, or even microwave weapons. (Read more Cuba stories.)