Memories can survive cryogenic preservation, study shows
Could our brains stay forever young? Memories can survive
cryogenic preservation, study shows
Research claims worms retain memories after undergoing
cryonic process
Nematodes were taught to react to the smell of
benzaldehyde before being frozen for 30 minutes and then their memories of the
smell were tested
Some scientists have expressed concern that the cryogenic
process can damage the delicate neural structures in the brain, wiping memories
By Richard Gray for MailOnline
Published: 12:16 EST, 2 June 2015 | Updated: 21:01 EST, 2 June 2015
It is a technology that has remained firmly in the realms
of science fiction, but new research has provided hope for those hoping to be
revived after being cryogenically frozen.
The study claims to have shown for the first time that
memories formed before an animal has been frozen can survive intact after it
has been thawed.
While the experiments were carried out in an organism
with a somewhat simpler brain than humans – nematode worms – they answer an
important question about the cryogenic process.
Overall there are not many creatures capable of being
revived after being cryogenically frozen, and it has never been successfully
achieved with any mammal.
However, if they could be reanimated, scientists have
questioned whether the memory and personality of someone who had gone through
the process would remain the same.
The freezing process can cause damage to cells if not
conducted without cryopreservative chemicals, and the effects of these is not
well understood.
LEECH CAN SURVIVE BIG FREEZE
A leech has been found to be able to survive after being
submerged in liquid nitrogen.
Ozobranchus jantseanus, a parasite found inside
freshwater turtles, can be successfully reanimated after exposure to an
astonishing -196°C for 24 hours.
It can also survive in temperatures of -90°C for nearly
three years.
The discovery was made by a team of Japanese scientists
who found a still-living leech attached to a frozen turtle.
Most organisms expire after freezing because of the
damage caused by the water in their cells when it freezes.
The new findings, conducted by researchers working for
the cyronics industry, reveal that, in worms at least, memories stored in the
brain can survive the process.
Natasha Vita-More, a researcher for the Alcor Life
Extension Foundation in Scottsdale, Arizona, said: 'This is the first evidence
of preservation of memory after cryopreservation.
'Further research on larger organisms with more complex
nervous systems could prove to be beneficial to the issue of cryopreservation,
including, specifically, memory retention after reviving.'
Worldwide there are only an estimated 300 people who have
undergone cryopreservation after they have died in the hope that they can be
revived using future technology.
However, the industry is extremely controversial and has
attracted criticism from scientists.
Although a popular theme in science fiction movies such
as Forever Young, Demolition Man and Austin Powers, it has never been possible
to successfully revive a human or any mammal.
Some species of frog, arctic fish and insects are able to
survive multiple freezing and thaw cycles because they have a naturally
occurring antifreeze in their cells that protect them from ice.
In other animals, freezing causes the growth of ice
crystals that can burst or damage their cells.
In an attempt to combat this the cryonics industry has
developed chemicals to protect the cells. Using techniques like vitrification –
rapid cooling – can also help reduce damage.
This has allowed scientists to preserve mammalian cells
and even an entire organ from a rabbit before reviving them, but never for a
whole body.
The impact of using these techniques on the delicate
structures of the brain has also been a subject of increasing debate.
To answer this Dr Vita-More and Daniel Barranco of the
University of Seville, and the CryoBioTech research group at the University of
Seville, trained the nematode worm Caenorhabditis elegans to respond in
specific ways when they smelled benzaldehyde.
In a series of experiments, published in the journal
Rejuvenation Research, they placed trained and untrained worms through
different cryopreservation methods.
They found that while only a third of the worms that were
preserved using a slow freezing method compared to those frozen using
vitrification, both groups retained memories of how to respond to the
benzaldehyde smell.
The worms were left frozen for 30 minutes before they
were thawed.
The results showed those worms which had been
cryogenically frozen equalled those that had not been frozen at all in tests of
their memory for the smell.
The researchers said: 'We demonstrated that
cryoprotectants used in both the slow freezing and vitrification processes do
not affect, alter, or change the mechanism that regulates the olfactory
imprinting and long-term memory.
Secondly, we determined that the process of
cryopreservation methods of slow freezing or vitrification do not affect,
alter, or change this mechanism.'
THE WEIRD WORLD OF CYRONIC PRESERVATION
The Alcor Life Extension Foundation in Arizona charges
around $200,000 for a person's body to be frozen after they die.
The industry is being fueled by the hope that as medical
science advances, it may be possible to bring the dead back to life.
Among those whose remains are frozen in the liquid
nitrogen containment tanks of Alcor's facility is the legendary Boston Red Sox
baseball player Ted Williams.
His family spent $100,000 to have the baseball legend’s
remains sent to a cryonics lab in Arizona.
Alcor Life Extension is the world’s largest cryonics
company, and it claims it is signing up customers from all over the world who
want their bodies preserved when they die.
It is illegal to place a living human into cryonic
preservation and it is only carried out once a client has been declared dead.
While some chose to preserve their whole body, others opt
for freezing just their brain at a cost of $80,000 in the hope it can be
transplanted into a living body.
The preservation process begins by moving a body to an
ice bed and cover them in a loose, slushy layer of ice.
A device called a 'heart-lung resuscitator’ is used to
get the blood pumping through the body again, and medication is applied to the
body to prevent the cells from deteriorating.
Next as much blood and bodily fluids are drained, then
they are replaced with a solution like antifreeze.
Major blood vessels are then flushed of any blood then
they are swabbed with the antifreeze solution.
The antifreeze solution is used so that ice crystals do
not form and damage any cells.
The body is then cooled down to about 0.5 degrees celsius
every hour until the final temperature of -195 degrees celciusis achieved over
three weeks then the frozen body is stored.
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