Unexplained Havana Syndrome Shows No Signs of Neurological Damage

Two recent brain-imaging studies have revealed that the mysterious illness that affected US diplomats abroad in 2016 did not result in any long-term brain damage. Referred to as Havana syndrome, this peculiar condition often manifests as dizziness, headaches, and blurred vision, along with other neurocognitive symptoms. However, the root cause of this illness continues to baffle scientists.

When the first cases were reported among government staff at the US embassy in Havana, Cuba, theories regarding the nature of the syndrome started to circulate. People reported experiencing loud noises and feeling pressure in their heads, which later led to the development of various symptoms, including difficulty sleeping.

Workers at other American embassies in China and Austria quickly reported these unusual health incidents, which US health officials had identified. Numerous observers, including well-known politicians, began spreading the idea that the illness was the result of a pulsed energy attack despite the lack of supporting evidence. However, the specific type of weapon capable of producing these symptoms remains uncertain.

In a study published in 2019, it was discovered that individuals experiencing Havana syndrome exhibited decreased white matter and functional connectivity in the auditory and visuospatial subnetworks of the brain, further intensifying the feeling of panic. However, a pair of new studies have recently challenged this data by not finding any clinical differences between individuals with the condition and healthy controls.

A study was conducted involving 81 individuals who experienced Havana syndrome and 48 individuals who were unaffected. After conducting magnetic resonance imaging (MRI) scans on each participant, no significant differences in brain structure or function were found between the two groups.

“Based on the results, it can be inferred that the AHI group did not show any signs of extensive brain lesions from a structural MRI perspective,” they state. Significantly, subsequent scans also indicated that the brains of individuals affected by Havana syndrome remained consistent over time, indicating the absence of developing abnormalities.

The researchers concluded that the absence of evolving lesions may suggest the absence of an acute brain injury, as most injuries tend to result in changes over time. Nevertheless, they emphasize that the absence of a neuroimaging signature of brain injury in this AHI cohort does not diminish the gravity of the clinical condition.

For the second study, MRI scans of 86 individuals with Havana syndrome were compared to those of 30 control subjects. Once again, there were no noticeable variations between the two groups.

With a scientific mindset, the authors carefully analyze their data and conclude that the absence of evidence for a brain injury does not automatically imply that no injury exists or that it didn’t happen during the AHI. In addition, it is worth mentioning that even though there was no brain damage observed, a significant portion (28 percent) of individuals with the syndrome exhibited symptoms of “functional neurological disorders” like persistent postural-perceptual dizziness (PPPD).

The researchers suggest that individuals with AHIs may be experiencing symptoms of PPPD and other related conditions, which could be attributed to a previous injury that is no longer detectable.

In the end, both studies fail to provide a definitive answer to the mystery behind the illness. The authors of the second paper contend that, in the event that a directed energy “attack” occurs, symptoms seem to be caused without any discernible or long-lasting physiological changes.

The two studies have been published in the Journal of the American Medical Association.