In 2015, residents from two villages in Kazakhstan dubbed as "sleepy hollow," were relocated after 25% of the population suffered a mysterious sleeping disease for three years already.

People who were hit by this bizarre sickness fell unconscious for days, made some mild-mannered pensioners swear, and men were having unusually high sex drives, Daily Mail reported.

Even authorities and experts were baffled at what caused the villagers to suddenly fall into the sleeping sickness. Some had hallucinations, especially children who reported seeing bizarre images. For instance, a girl reported seeing an elephant trunk on her mother and a boy who imagined horses and light bulbs dancing around his head.

Kazakhstan's 'Sleepy Hollow': Was It Magic Or Science? Uncovering the Mystery Of the Two Villages Who Fell Asleep
(Photo: Wikimedia Commons)
Baiken Uranium Mine in Kazakhstan

Lack of Oxygen in Sleepy Hollow

According to IFL Science, uranium mines from the Soviet Union era that have long been closed were one of the suspected causes of the mysterious sleeping disease. But mass testing showed no significant amounts of radiation in households.

Some also believe that it could be the tainted alcohol or perhaps a form of mass hysteria. However, the latter suspicion was not accepted because even Marquis the cat was affected, an animal that is not known to be susceptible to mass hysteria.

"He seemed to be foolish, throwing himself against the walls, cabinets, meowing," Elena Zhavoronkova said in an interview with in 2015. "He tortured us until three in the morning. They took him out to the veranda, where there was a dog, so the Marquis began to rush at it."

In the end, it was found out that the lack of oxygen in the brains of those affected villagers was the cause of why they were suddenly falling asleep. The lack of oxygen in the two villages was attributed to the uranium mines and not radiation poisoning.

Deputy Prime Minister Berdibek Saparbaev said in 2015 that the uranium mines, although have been closed for some time, continue to release a concentration of carbon monoxide in the air that reduced the oxygen levels, causing sleeping sickness.

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What Happens When Brain Lacks Oxygen?

When oxygen is not enough and carbon monoxide is abundant, the latter binds to hemoglobin instead of the former and produces carboxyhemoglobin that leads to a lower supply of oxygen to the brain.

This then causes the condition called cerebral hypoxia that affects the cerebral hemispheres, which is the largest part of the brain, according to Medline Plus. The term also describes the lack of oxygen supply in the entire brain.

It could be caused by breathing in smoke, carbon monoxide poisoning, high altitudes, cardiac arrest, stroke, and low blood sugar.

Since brain cells are very sensitive to the lack of oxygen, some start dying within five minutes after the oxygen supply has been cut. This could result in severe brain damage or death.

The abundance of carbon monoxide from the uranium mines explains the situation of Kazakhstan's sleepy hollow. The villagers were already evacuated and relocated to avoid further cases.

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