Nearly 12,000-year-old human brains found intact

A study led by anthropologist Alexandra Morton Hayward and her team from the University of Oxford has shown that the human brain can survive the corrosive force of time, lasting much longer than scientists previously thought.

The results show that human brains are surprisingly resistant to decomposition, a hypothesis that stands in stark contrast to previous theories.

For the project's needs, the researchers asked archaeologists from around the world, creating a global archive where experts could compare individual files – some of them specimens – from more than 4,400 preserved human brains. These brains were collected from a variety of environments, from the frozen lands of the Arctic to the deserts of ancient Egypt, challenging the idea that the brain is one of the first organs to decompose.

The team behind the new study “scoured” archaeological archives of more than 4,000 human brains, many dating back 12,000 years, to determine the truth about brain decay.

Overturning the old idea of ​​rapid brain decay

The brain is usually one of the first organs to decompose after death. Thus, the prevailing perception is that naturally preserved brains are “one-of-a-kind” or “extremely rare” finds, especially in the absence of other soft tissue. However, recent research challenges these notions, showing that preserved brains exist in much larger quantities than previously thought, thanks to conditions that prevent decay.

Morton Hayward says these ancient brains may be an untapped source of information about our past.

What ancient minds reveal

The preserved brains were found in a different state. Some were brittle and dry, having lost all their moisture, while others were soft and spongy. Surprisingly, a large portion of these brains were discovered in bodies in which no soft tissue was preserved, which constitutes an unusual phenomenon in the field of archaeological discoveries.

Cases in which the brain remains intact

Morton Hayward explained to Science: “Normally, the brain liquefies immediately after death. However, there have been some autopsy cases where the brain has remained intact, like jelly inside the skull. Browsing through the literature, I was surprised by the numerous examples of preserved brains.

Eventually, thousands were found, dating back 12,000 years, and from every continent except Antarctica. However, no one is looking into this article..

The ability to preserve the brain for a very long time

“I think the amazing element of the research is that although we know that the brain can liquefy quickly, in some cases, it can arguably be preserved for incredibly long periods.” Morton Hayward explained, speaking to Science magazine.

“I would argue that we need to start thinking more deeply about soft tissue preservation.”

The mystery that remains

Although less than 1% of the archive is studied today, the sheer volume of preserved brains has created new research opportunities. Factors such as freezing, tanning and dehydration that help preserve the brain are carefully studied. However, what keeps the brain alive, while the rest of the organs decompose, remains a mystery. The solution to this puzzle can be found in the unique chemical composition of the brain, especially in the balanced ratio of proteins to lipids, which can interact with environmental factors such as minerals and thus facilitate their preservation.

As such, Morton Hayward's ongoing research is an “untapped archive” that can shed light on human evolution and help us better understand health and disease since ancient times. The research could also provide insight into neurodegenerative conditions affecting people today, such as Alzheimer's disease and other forms of dementia.

A revolution in understanding neurological disorders

As Morton Hayward observed, “Old brains may provide new insights.” This research has the potential to revolutionize our understanding of evolution and neurological disorders by revealing details about the health and lifestyles of our ancestors.

The study was published in Royal Society for Biological Sciences.