The U.S. intelligence community released a report Wednesday saying it is “very unlikely” a foreign adversary is responsible for abnormal afflictions known as “Havana syndrone” reportedly plaguing agents.

Havana syndrome refers to brain injuries of unknown origin, marked by symptoms including headaches, memory and cognition problems, hearing and vision loss, and dizziness.  The official report said that the idea that the symptoms were perpetrated by Russia or other U.S. adversaries was “not borne out by subsequent medical and technical analysis.”

“In light of this and the evidence that points away from a foreign adversary, causal mechanism, or unique syndrome linked to AHls, IC agencies assess that symptoms reported by U.S. personnel were probably the result of factors that did not involve a foreign adversary, such as preexisting conditions, conventional illnesses, and environmental factors,” the Office of the Director of National Intelligence wrote.

The report did acknowledge that “IC agencies have varying confidence levels because we still have gaps given the challenges collecting on foreign adversaries – as we do on many issues involving them.”

The conclusions of the report concur with previous findings that have doubted the use of speculative “energy weapons” or devices to incapacitate targets.