"Study: No Physical Evidence of Brain Injuries in 'Havana Syndrome' Patients"
Originally Published 1 year ago — by PBS NewsHour

A five-year study by the National Institutes of Health found no evidence of brain injuries or degeneration among U.S. diplomats and government employees experiencing symptoms of the mysterious "Havana syndrome." The study contradicted earlier findings and did not provide an explanation for the symptoms, which include headaches, balance problems, and cognitive difficulties. While some patients were diagnosed with a balance problem called PPPD, the study did not find significant differences in brain volume or cognitive tests. The cause of the symptoms remains unknown, and the study was not designed to examine the likelihood of a specific weapon or trigger for the syndrome.
