Diplomats serving at the U.S. Embassy in Cuba “appeared to have sustained injury to widespread brain networks” there, according to physicians who evaluated them for the State Department.

But the physicians could find no definitive cause for their ailments, they said in an article in Thursday’s edition of the Journal of the American Medical Association.

The article, written by specialists at the University of Pennsylvania’s Perelman School of Medicine, provided the most detailed description to date of the injuries – including headaches, dizziness and hearing, vision, sleep and mood disorders. The specialists examined 21 of 24 diplomats who reported symptoms between late 2016 and last August.

The State Department has charged that its personnel were targeted for specific “attacks” while in Cuba. Late last year, the Trump administration ordered the withdrawal of more than half of the embassy’s diplomats and their families from Havana and advised Americans not to travel there. A similar number of Cuban diplomats were expelled from their embassy in Washington.

Controversy over the medical issues coincided with President Donald Trump’s implementation of policy changes reversing parts of the Obama administration’s normalization of relations with Cuba in 2015. The new rules, fulfilling a Trump campaign promise to roll back what he called a “terrible” policy, imposed new restrictions on trade and travel to Cuba.

Cuban officials have repeatedly denied responsibility for any attacks on the diplomats, and have said the United States has provided little substantive information for them to investigate the complaints.

Some U.S. officials have speculated that the “attacks” could have been conducted by “rogue” elements within the Cuban government or military, or by agents of an unidentified third country.

The clinicians examined 11 women and 10 men, with an average age of 43, whose evaluations began an average of 203 days after they first noticed symptoms, the article said.

In most cases, the affected diplomats reported hearing a loud, painful noise that they later associated with their symptoms. “For 18 of the 21 individuals,” the JAMA article said, “there were reports of hearing a novel, localized sound at the onset of symptoms in their homes and hotel rooms” in Havana. “Affected individuals described the sounds as directional, intensely loud, and with pure and sustained tonality,” although some described it as high pitched, and others said it was low pitched.

“The sounds were often associated with pressurelike or vibratory sensory stimuli … likened to air ‘baffling’ inside a moving car with windows partially rolled down,” the report said. Some, it said, were awakened by the sound, which was variously said to have lasted seconds or longer than 30 minutes. Some reported immediate neurological symptoms, while others noticed nothing until days or weeks afterward.

(c) 2018, The Washington Post · Karen DeYoung