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Immortality - Humans have always been captivated by the idea of eternal life. We are mortal beings, and the knowledge of our inevitable end can be a difficult truth to embrace.

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Cheating death -

In the hopes of beating death, cryogenic freezing was one method a few scientists started to dabble with in the '60s. It promised that scientists would be able to stop the dying process. When a cure for whatever ailment that caused the death was found, bodies would be defrosted back to life.

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Cryogenics becomes popular -

In 1962, scientist Robert Ettinger published the book 'The Prospect of Immortality,' which popularized the idea of freezing human bodies to extend their lives. He is now considered the "father of cryogenics."

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Close family -

Although controversial and disputed by other scientists, the method has already been used. Ettinger reportedly had his mother, his first wife, and his second wife cryogenically frozen and stored in vats at his Cryonics Institute.

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Not guaranteed -

It's still considered a huge gamble. There's no certainty about when one would wake up. Some say 50 years, others say hundreds. The plan is to keep people frozen until a cure for the cause of death, or aging in general, is discovered.

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Risks - The technique's practical viability has been questioned, especially since cryoprotectants like glycerol are used in the process. These substances are highly toxic, and it's uncertain how they will affect cells during the thawing process.

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Risks -

Without these toxic protective agents, however, it's impossible to freeze the body. When cells freeze, they form large ice crystals that destroy cell walls.

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Ethical questions -

The method was also always surrounded by ethical questions, not just about life and death but also about the responsibilities of cryonics providers and the rights of cryopreserved individuals.

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Tricky brain -

One of the main concerns raised by critics of cryogenics is the brain. Since it's composed of millions of neural pathways, it's difficult to imagine that the freezing process wouldn't damage these delicate connections.

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Dangerous -

Critics of cryogenics argue that even if the body could be revived, the level of brain damage would make life hardly worth living.

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Still a possibility -

However, a recent poll of 300 neuroscientists revealed that 40% of them believe it's possible to one day resurrect memories from preserved brain structures, and perhaps even fully emulate a brain.

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Scientists bet on it -

Ariel Zeleznikow-Johnston, a neuroscientist from Monash University in Australia and the instigator of the poll, believes that technology has advanced enough to make brain preservation worth considering. He would choose cryopreservation if he knew he was dying and had the chance.

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Not retroactive -

However, he said, this doesn't mean we'll be able to chat with the dozens of people who have already undergone cryopreservation.

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Brain damage -

Zeleznikow-Johnston argues that most previous techniques, like those used in the 1960s, would have destroyed brain structures. Only recently have we developed methods capable of preserving connectivity patterns.

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Taking it slow - Even though there are apparently viable methods available, the scientific community remains cautious about the process.

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Still taboo? -

Zeleznikow-Johnston is under the impression that "many colleagues consider ideas like brain preservation, structural encoding of memory, and even mind-uploading plausible, but they don't want to discuss them publicly."

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Memory storage -

Part of the argument, he said, concerns how memories are stored. Do they exist solely in the connectivity patterns of neurons, or is more information required—perhaps at the atomic level, hormonal, or electrical?

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Complex structure -

There seems to be a growing consensus among neuroscientists that the brain's structural properties are crucial for storing information, according to Zeleznikow-Johnston, who also wrote 'The Future Loves You: How and Why to Abolish Death.'

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How to preserve memories? -

In particular, he cites deep hypothermic circulatory arrest, a technique that involves cooling patients before surgery to protect the brain.

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How to preserve memories? -

This stops electrical activity in the brain, but memories reportedly remain intact.

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Keeping your ID -

"There's strong evidence that preserving a person's brain would preserve their key personal identity," said Zeleznikow-Johnston.

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More complex -

Professor Timothy O'Leary from the University of Cambridge, a polled neuroscientist, acknowledges the potential of detailed brain mapping but cautions that it doesn't guarantee functional revival. He argues that this limitation applies to any complex physical system, not just the brain.

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Already done -

This reality is closer than we might think. The brain of Li Zehou, one of China's most renowned modern philosophers, has been preserved in a leading US cryonics facility since his death in 2021.

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Passing it on -

The philosopher expressed his desire to preserve his brain as early as 2010, telling the domestic media outlet Southern Weekly that he hoped it could be studied for clues about Chinese culture.

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Facilities -

Li's biographer, Ma Quanlin, said the late professor's brain was frozen at the Alcor Life Extension Foundation in Arizona after his death.

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How much does it cost? -

According to the center's website, whole-body cryopreservation costs U$220,000, while brain cryopreservation costs $80,000.

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Misplaced memories -

O'Leary highlights the complexity of capturing detailed neural patterns that form memories, arguing they require a functioning nervous system and potentially a physical body to manifest. Measurement errors could result in partial or inaccessible memory storage.

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A "future you" problem -

To illustrate this idea, The Times compares it to waking up after a century only to discover that a measurement error has prevented you from accessing your life savings because the "revived you" forgot your PIN.

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Next steps -

As scientists continue to explore the possibilities of brain and body preservation, discussions about regulation are also ongoing. An international conference on human cryopreservation, or biostasis, was held in Madrid in November 2022 to discuss a regulatory framework for future procedures.

Sources: (The Times) (Sixth Tone) (Alcor Life Extension Foundation)

See also: Peculiar ways to become immortal

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