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NIH: No evidence of brain injury in ‘Havana syndrome’

March 18, 2024

Since 2015, many US government personnel serving internationally have described unusual incidents of intrusive noise and head pressure, often in conjunction with headache and cognitive changes. Initially, the constellation of symptoms was labeled “Havana syndrome” due to a concentration of cases in Cuba. However, as similar reports surfaced in other countries, the US government labeled these events "anomalous health incidents" (AHIs).

Now, in two studies published in JAMA, researchers have reported finding no evidence of brain injury or biological abnormalities among U.S. federal employees who've been experiencing AHIs.

"These individuals have symptoms that are real, distressing and very difficult to treat," Dr. Leighton Chan, NIH Clinical Center acting chief scientific officer and lead study author, said on a call to discuss the findings. (Beasley, 2024)

While many of the symptoms still are not easily explained, the U.S. intelligence community concluded last March that it was "very unlikely" that the health incidents were the result of an attack from a foreign adversary—a theory initially posited by many U.S. officials and lawmakers. The agencies suggested in that report that symptoms reported by U.S. personnel were likely the result of pre-existing conditions, conventional illnesses, and environmental factors. (Fortinsky, 2024; Beasley, 2024)

However, not all agree that the JAMA studies provide enough evidence to refute foreign adversary involvement. Mark Zaid, an attorney representing AHI victims, notes that these studies "do nothing to undermine the theory that a foreign adversary is harming U.S. personnel and their families with a form of directed energy.” (Fortinsky, 2024)

Study findings

The studies, published in JAMA, are the result of a nearly five-year probe by the NIH seeking to evaluate differences between a healthy control group and federal employees who experienced symptoms associated with AHIs.

In the first NIH exploratory study that involved brain imaging of 81 participants who experienced AHIs and 48 matched control participants, no significant between-group differences were seen in MRI measures of volume, diffusion MRI–derived metrics, or functional connectivity using functional MRI after adjustments for multiple comparisons. The MRI results were highly reproducible and stable at longitudinal follow-ups. No clear relationships between imaging and clinical variables emerged. (Pierpaoli, 2024)

Carlo Pierpaoli, lead author on the neuroimaging study, said while there is no evidence of brain injury on the MRIs, it's still possible that those reporting AHIs “may be experiencing the results of an event that led to their symptoms, but the injury did not produce the long-term neuroimaging changes that are typically observed after severe trauma or stroke.” (Fortinsky, 2024)

The second NIH study included 86 participants reporting AHIs and 30 vocationally matched control participants. Study participants, including personnel who'd been stationed in Cuba, China, Vienna and the United States, underwent a battery of clinical, auditory, balance, visual, neuropsychological and blood testing. No significant differences were found between the two groups for most clinical measures. (Chan, 2024)

However, participants with AHIs performed significantly worse on self-reported and objective measures of balance, and had significantly increased symptoms of fatigue, posttraumatic stress disorder, and depression compared with the control participants; 24 participants (28%) with AHIs presented with functional neurological disorders. (Chan, 2024)

Sources:

Beasley Deena. (2024, March 18). Reuters. No evidence of Havana syndrome brain injury, US studies find. https://www.reuters.com/world/us/us-study-finds-no-evidence-havana-syndrome-brain-injury-2024-03-18/

Pierpaoli C, et al. (2024, March 18). JAMA. Neuroimaging Findings in US Government Personnel and Their Family Members Involved in Anomalous Health Incidents. https://pubmed.ncbi.nlm.nih.gov/38497822/

Chan L, et al. (2024, March 18). JAMA, Clinical, Biomarker, and Research Tests Among US Government Personnel and Their Family Members Involved in Anomalous Health Incidents. https://pubmed.ncbi.nlm.nih.gov/38497797/

Fortinsky, Sarah. The Hill. (2024, March 18). The Hill. NIH researchers find no evidence of 'Havana syndrome' in brain scans. https://thehill.com/policy/healthcare/4539463-nih-researchers-find-no-evidence-of-havana-syndrome-in-brain-scans/