When it comes to death, there's traditionally been two forms of eternal rest: going into a coffin or ending up as ashes inside an urn.
But some are embracing a third way – having their body or brain frozen in liquid nitrogen in the hope of some day being brought back to life, with memories, personality and sense of self intact.
"I believe that my identity is stored inside my physical brain," says Carrie Wong, president of the Lifespan Society of British Columbia, an advocacy group that works to promote and protect access to cryonic preservation.
"So if I can somehow preserve that, maybe at a future time technology and medical science will advance to such a point that it may be possible to repair the damage of freezing me in the first place and also what killed me back then," says the 27-year-old, who concedes such a feat could be hundreds of years in the future.
"It's not possible now, but nobody can really argue it's not possible in the future, because that's arguing about what future technology is capable of."
The notion that a person could be frozen and later "reanimated" was initially posited in the 1964 book The Prospect of Immortality by American physics teacher and sci-fi writer Robert Ettinger.
The first person to be cryonically preserved was Dr. James Bedford, a 73-year-old California psychology professor, whose body was suspended in liquid nitrogen in 1967 at Alcor Life Extension Foundation in Scottsdale, Ariz.
Alcor's most famous "patient," as they're called, is Red Sox baseball legend Ted Williams, whose head was detached from his body and cryopreserved after the slugger's death at 83 in 2002.
After a person is declared legally dead, the body is cooled in an ice bath and hooked up to a machine to artificially restore blood circulation and breathing, and infused with blood thinners and other medications to protect the brain from lack of oxygen.
Blood and other fluids are later drained from the body and replaced with a cocktail of cryoprotectant chemicals. These antifreeze-like agents are intended to prevent the formation of damaging ice crystals in cells, in a process known as vitrification.
The body is then further cooled before being suspended in a tank of liquid nitrogen at a bone-chilling -196 C.
The Cryonics Institute, a non-profit organization founded in 1976 by Ettinger, operates a preservation facility near Detroit, where about 100 pets and 135 humans are suspended in tanks called cryostats.
"The actual cryostats are just giant thermos bottles with liquid nitrogen; there's no electricity to fail," says president Dennis Kowalski, a 47-year-old Milwaukee firefighter and paramedic who became interested in cryonics in his 20s after reading K. Eric Drexler's 1986 book Engines of Creation, about the coming era of nanotechnology.
About 1,250 people, including a number of Canadians, are signed up for CI's service. Membership costs $28,000 (U.S.), which is typically paid for through life-insurance policies.
While acknowledging that he and others who intend to be frozen are often "looked at as a bunch of kooks," Kowalski views cryonics as being like a clinical experiment – and one that beats the alternative.
"I'll be the first to admit it may not work. And everyone who's signed up should understand cryonics may not work and there are no guarantees."
CI doesn't provide "neuros," in which only the head and brain are preserved. Even so, bodies are placed in the cryostats upside-down, based on the theory that if a catastrophe were to threaten the tanks' viability, "the brain would be the last to go."
"We place emphasis on the importance of the brain because even under today's crude technology, you probably could clone a human being and replace every single part," suggests Kowalski.
"But one thing you can't replace is your mind – which is you – and your mind is somehow encoded in that brain, and that's what we hope to principally save."
Christine Gaspar, 42, an emergency room nurse from Amaranth, Ont., northwest of Toronto, is a CI member and president of the Cryonics Society of Canada, an educational and advocacy organization.
"My parents and my sister are also signed up. It took me about five minutes to convince my father and it took me about 15 years to convince my mother and my sister, but I finally got it done.
"I actually cryopreserved my cat two years ago [for a fee of $5,800 (U.S.)]," Gaspar confides. "I know it sounds extraordinary, but if it's something that you believe in philosophically, then you do it for what you love and who you love."
She's part of a Toronto-area group on standby for any dying Alcor or CI member, so initial preservation can begin soon after death and before a cryonics-trained funeral director arrives to continue the process.
The deceased is then transported to the Michigan or Arizona facility, where vitrification is completed. Neither Alcor nor CI provide this service in Canada.
Cryonics, she proposes, is merely an extension of emergency medicine.
"What cannot be repaired today may be able to be repaired tomorrow. And instead of making a referral to a doctor in another city, you're making a referral to a doctor in another time."
Gaspar, who along with her family members is opting for whole-body preservation, has no idea what kind of society she might come back to should science discover a way to revive her in the future – and she doesn't care.
"I can learn. I can adapt."
Adherents aside, few self-respecting neuroscientists will even touch the topic of cryonics, given its speculative nature.
One who does is Ken Hayworth, a senior scientist at the Howard Hughes Medical Institute's Janelia Farm Research Campus in Virginia, who maps neurocircuits, the wiring in the brain where memory is stored at the most fundamental level.
"If there was some way to preserve people so they could get to the future, that would be a nice alternative to death as we know it," says Hayworth, co-founder of the Brain Preservation Foundation, formed to promote scientific research in the field.
"A lot of people are dedicated to doing it right," he allows. "At the same time, though, if you look at the level of evidence in the scientific literature – which is almost non-existent – there seems like there's a tremendous gap between how good it should be in the year 2015 and what is actually being done."
The foundation is offering a prize, currently at $106,000, to advance brain-saving technology. A quarter of the money will be awarded to the first international team to successfully preserve a whole mouse brain, with complete synaptic structure intact.
The remainder will go to scientists able to preserve the brain of a large animal, such as a pig, "in a manner that could also be adopted for humans in a hospital or hospice setting immediately upon clinical death."
Hayworth says current cryo techniques don't provide proof that synaptic circuitry is maintained, and for lack of evidence, he's given up his Alcor membership.
Of course, the next step would be finding a way to undo the effects of vitrification and return a person to life.
"The revival aspect is very far off in the future; I would put it at least 50 to 100 years off," says the neuroscientist, who believes memory, identity and personality are all encoded in the brain's circuitry, just as information and operating instructions are stored on computer chips.
"If we're talking about 100 years from now, I think people will have been almost forced by practical considerations into becoming more and more wedded with machines," he predicts. "We'll have machines implanted in our brains, we'll have body parts that are replaced with mechanical parts and we will say, forget biology altogether."
Tim Caulfield, a health law expert at the University of Alberta, says putting a person's body on ice in the hopes of future rejuvenation raises all kinds of legal and ethical issues.
"What if the company goes bankrupt, 10 or 15 or 25 years from now? What happens to those bodies? Who has control over those bodies?"
And if future scientists do thaw out and manage to return their very first human to life, what would be the quality of that life? What if that person ended up cognitively or physically disabled? Could they sue the company?
"The science is very speculative at this point," insists Caulfield. "That raises some interesting questions about marketing these services to people and having them invest significant portions of their money, their estate to these projects.
"People can do whatever they want with their money. But they should go in with their eyes open."
In a bid to protect consumers, British Columbia became the only jurisdiction in North America to prohibit the marketing of cryonic services based on the expectation of resuscitation at a future date – a regulation the Lifespan Society is challenging in provincial court.
Wong of Lifespan says the law has had a chilling effect on cryonic-related services, which her group hopes to help expedite in the future.
"It's deterred some funeral directors from working with cryonicists in B.C.," says Wong, who has signed on with Alcor for a "neuro."
"It hinges on what people mean by expectation. You would have some expectation or some belief that it could work or we wouldn't be doing it."
Keegan Macintosh, the co-plaintiff in the case that is yet to be heard, believes he has the right to decide what happens to his body after death.
The Vancouver public-speaking and drama instructor sees his reasons for assigning Alcor $80,000 (U.S.) of life insurance benefits to have his brain cryopreserved as strictly pragmatic.
"It's as simple as the fact that I love life. For now I don't foresee a time in the future where I won't want to wake up for another day," says Macintosh, though he dismisses the idea that cryonicists are seeking immortality.
"I don't view the other alternative as having any chance of resulting in some continued life after I'm dead," he says of burial or cremation.
And although the science of cryonics is still in its infancy, Macintosh thinks it's worth the gamble.
"Maybe the chances aren't very big, but they're big enough for me to place my chip there."
Some facts about cryonic preservation
Here are some facts about cryonics, the process of freezing the body after death in the hope that scientific advances will allow a person to be "reanimated" in the future:
HOW IT'S DONE
As soon as possible after a person is declared legally dead, the body is cooled in an ice bath and hooked up to a machine, known as a "thumper," to artificially restore blood circulation and breathing while blood thinners and other drugs are administered intravenously to protect the brain from lack of oxygen.
Blood and other fluids are subsequently drained from the body and replaced with a cocktail of vitrification, or antifreeze-like agents, to prevent the formation of damaging ice crystals in cells and tissues.
The body is then further cooled before being suspended in a tank of liquid nitrogen at -196 C.
WHO DOES IT
There are two major non-profit cryopreservation facilities in the United States that Canadians can join.
The Cryonics Institute facility near Detroit has cryopreserved about 135 people and 100 pets, mostly dogs, cats and birds. Human cryopreservation costs $28,000 (U.S.). Most people pay for the service through life insurance policies.
The Alcor Life Extension Foundation in Scottsdale, Ariz., will preserve the head and brain – called a "neuro," for $80,000. Whole-body preservation costs $200,000. The company has cryopreserved more than 135 "patients" and has more than 1,000 members signed up for its after-death service.
Its most famous "client" is former Red Sox slugger Ted Williams, whose head was suspended in liquid nitrogen in 2002 after his death at 83.
WHERE THE SCIENCE IS
It's not clear if current cryo techniques maintain the pristine neurocircuitry of the brain that would allow a person to be brought back to life, a feat that even cryonicists admit could take many decades to master, if not hundreds of years, if it is possible at all.