01. July 2016 · Comments Off on Advances in Cryoprotectant Toxicity Research · Categories: Cryonics, Science

There is little disagreement among cryobiologists that the biggest limiting factor to reversible organ cryopreservation is cryoprotectant toxicity. It is actually not that hard to create vitrification solutions that completely inhibit ice formation at even the slowest cooling rates. The problem is that such highly concentrated vitrification solutions are too toxic to permit recovery of complex tissues. The least toxic vitrification solution for complex mammalian organs as of writing is M22. M22 is the culmination of many years of experimental and theoretical work by cryobiologist Greg Fahy and colleagues using rabbit kidney slices. Studying selected cryoprotectant mixtures on rabbit kidney slices, Fahy and colleagues came to the following conclusions:

1. High concentrations of a cryoprotective agent (or a mixture of different cryoprotective agents) can prevent ice formation during cooldown and warming.

2. The toxicity of some cryoprotectants can be neutralized by combining them with other cryoprotective agents.

3. The non-specific toxicity of a  cryoprotectant solution can be predicted by calculating a quantity (“qv*”) which is intended to measure the average hydrogen-bonding strength of the cryoprotectant polar groups with the water molecules in the solution.

4. Within limits, non-penetrating agents can reduce the exposure of cells to toxic amounts of cryoprotectants without reducing vitrification ability.

5. Synthetic “ice blockers” can be included in a vitrification mixture to reduce the concentration of toxic cryoprotective agents necessary to achieve vitrification.

While M22 is a low toxicity solution, its toxicity profile still necessitates minimizing exposure time and introduction and removal at low (subzero) temperatures. If we had a better understanding of the mechanisms of cryoprotectant toxicity, vitrification solutions with no toxicity at all could be introduced at higher temperatures and exposure times could be increased to optimize complete equilibration of the tissue with the cryoprotectant. It would also allow safer storage at intermediate temperature temperatures (around -130 degrees Celsius) because ultra-stable vitrification solutions could be used that are less prone to de-vitrification upon re-warming. This would be of particular interest for the cryopreservation of large organs or even whole organisms (with applications such as suspended animation and cryonics).

Two major reviews of cryoprotectant toxicity were published in the last 5 years; Gregory Fahy’s “Cryoprotectant Toxicity Neutralization” (Cryobiology, 2010) and Benjamin Best’s “Cryoprotective Toxicity: Facts, Issues, and Questions” (Rejuvenation Research, 2015).

Greg Fahy’s paper is a rigorous exposition of experimental results concerning the phenomenon of cryoprotectant toxicity neutralization. The paper is mostly limited to the discovery that DMSO can block the toxic effects of amides such as formamide. The combination of DMSO and formamide (or other amides such as urea and acetamide) is indeed one of the building blocks of M22 but this combination cannot be used without limit and the paper includes data that indicate the maximum molar concentrations (and ratios) that still permit full viability. In theory, if two (or more) cryoprotectants would completely neutralize each other’s toxicity they could be the sole components of a vitrification solution. But as the formulation of M22 shows, it is still necessary to add weak glass formers such as ethylene glycol, extracellular CPA’s, and “ice blockers” to supplement the toxicity neutralization obtained with formamide and DMSO. An important finding in Fahy’s paper is that n-methylation abolishes toxicity neutralization for amides and combining methylated amides also does not lead to toxicity neutralization between them. In fact, Fahy found that the presence of n-methylated compounds renders even small amounts of DMSO toxic. The remainder of the paper discusses the mechanisms of cryoprotectant toxicity and Fahy now favors protein denaturation as a plausible mechanism of (non-specific) toxicity. While other cases of toxicity neutralization have been reported in the literature, no rigorous studies have been done to produce a body of knowledge that is comparible to what we know about amide-DMSO interactions.

Benjamin Best’s paper is more general in scope but presents a lot of experimental data and also critically discusses Fahy’s work on cryoprotectant toxicity. As Ben Best points out, different (and seemingly contradictory) results do not necessarily mean that cryoprotectant toxicity is a species or cell-type dependent phenomenon. One could imagine a meta-analysis of cryobiology data in which variables such as concentration, loading- and unloading protocols, exposure temperature, exposure time, and the type of viability assay are matched to ensure methodological consistency. It is also important to compare cryoprotectants at their minimum concentration to vitrify to make meaningful toxicity comparisons. If the work at 21st Century Medicine is an indication, universal low-toxicity cryoprotective solutions should be feasible. Perhaps the most interesting part of the paper is where Best offers a critique of Grag Fahy’s “qv* hypothesis of cryoprotectant toxicity”, which aims to show that non-specfic toxicity concerns the degree to which cryoprotectants leave water available to hydrate macromolecules. This discovery allowed for the substitution of ethylene glycol for propylene glycol in Fahy’s lower toxicity vitrification solutions, despite the resulting higher CPA concentrations. Best observes, “it seems contradictory that water remains available for hydration, but not available for ice formation.” A potential rejoinder to this observation is that so called “bound water” does not participate in ice formation but can be disturbed by strong glass formers. Best also suggests a potential refinement of qv* that allows for more precise calculation of the hydrogen bonding strength of the polar groups that are used to calculate qv*. It is conceivable that such a refinement would eliminate the few remaining outliers in the data that support the qv* hypothesis. The paper also draws attention to the possibility of kosmotropic co-solvents and changes of pH and microenvironment polarity to mitigate cryoprotectant toxicity.

Neither of the papers discusses cryopreservation of the mammalian brain, but there is good reason to believe that in the case of this organ modification of low-toxicity vitrification solutions is required. Conventional cryoprotective agents such as PG, EG, and DMSO have poor blood brain barrier (BBB) penetration and the brain may not tolerate the CPA exposure times that other organs do. For example, while M22 can be used for cryopreservation of the brain, many of its component have poor BBB penetration and PVP and the ice blockers (X-1000 and Z-1000) are assumed not to cross the (non-ischemic) BBB at all. One potential solution is to (reversibly) open the BBB with so- called BBB modifying agents like detergents or perhaps to search for cryoprotective agents that can cross the BBB.

The most fundamental question in the design of vitrification solutions remains whether it is possible at all to introduce high concentrations of cryoprotectants without creating any kind of irreversible molecular and ultrastructural adverse effects. Understanding what specific and non-specific cryoprotectant toxicity exactly is should enable us to answer this question.

Originally published as a column (Quod incepimus conficiemus) in Cryonics magazine, September-October, 2016

09. February 2016 · Comments Off on Groundbreaking Scientific Results Prove that the Proposition of Human Medical Biostasis has Potential and Needs to be Brought into Mainstream Scientific and Medical Focus · Categories: Cryonics, News

Breaking News [Media Press Package with additional detail]

A team from 21st Century Medicine has developed a technology that has been independently verified to enable near-perfect, long-term structural preservation of a whole intact mammalian brain.

This new breakthrough just won the Brain Preservation Prize – five years after it was launched by the Brain Preservation Foundation (BPF).

“One of the, if not THE, most important scientific results in the history of medical biostasis and cryonics has been accomplished” Aschwin de Wolf, President of The Institute for Evidence-Based Cryonics

According to the BPF, 21st Century Medicine narrowly beat a team led by Dr. Shawn Mikula at the Max Planck Institute of Neurobiology (published last year in Nature Methods).

In addition to proof of this accomplishment and the full 21st Century Medicine “Aldehyde-Stabilized Cryopreservation” protocol recently being published in the journal Cryobiology, it was also independently verified by the BPF through extensive electron microscopic examination.






The prize was independently judged by neuroscientists Dr. Sebastian Seung, Professor at Princeton University and Dr. Kenneth Hayworth, President of the BPF.

“Imagine being able save, and at low temperatures, indefinitely preserve people who can no longer be sustained by contemporary medicine so that future medicine can both revive them and restore their health – these results provide strong support of that being possible”

Dr. JP de Magalhães, Chair of the UK Cryonics and Cryopreservation Research Network

This follows recent scientific evidence that long-term memory is not modified by the process of whole organism cryopreservation and revival in simple animal models.

As the two leading think-tanks/scientific networks in cryonics we share here a brief with both more color and our perspectives on what this important breakthrough means and – does not mean – for cryonics. 

In the words of Dr. Ken Hayworth, President of the Brain Preservation Foundation, and one of the prize judges:

“Every neuron and synapse looks beautifully preserved across the entire brain. Simply amazing given that I held in my hand this very same brain when it was a vitrified glassy solid… This is not your father’s cryonics”

09. February 2016 · Comments Off on Recent developments relevant to cryonics · Categories: Cryonics, Neuroscience

A lot of interesting pieces related to cryonics have appeared over the last few months that I thought I would share:

Four professors conclude in MIT Technology Review that there is significant and growing body of evidence in support of human cryopreservation: “The Science Surrounding Cryonics” 

New York Times Cover story by Pulitzer Prize winning journalist on “A Dying 23 Year Young Woman’s Hope in Cryonics and a Future”

Skeptic Michael Sherman writes a piece in Scientific American called  “Can Our Minds Live Forever?”

Here are three recent important peer reviewed papers:

Dr. Greg Fahy and Robert McIntyre of 21st Century Medicine describe here a new cryobiological and neurobiological technique, aldehyde-stabilized cryopreservation (ASC), which demonstrates the relevance and utility of advanced cryopreservation science for the neurobiological research community. The ASC technology is now also competing against Dr Mikula at Max Planck in he brain preservation prize.

The Grand Challenges of Organ Banking and It’s Potential is described by large group of the worlds leading cryobiology scientists:  The first Organ Banking Summit was convened from Feb. 27 – March 1, 2015 in Palo Alto, CA, with events at Stanford University, NASA Research Park, and Lawrence Berkeley National Labs. Experts at the summit outlined the potential public health impact of organ banking, discussed the major remaining scientific challenges that need to be overcome in order to bank organs, and identified key opportunities to accelerate progress toward this goal. Many areas of public health could be revolutionized by the banking of organs and other complex tissues, including transplantation, oncofertility, tissue engineering, trauma medicine and emergency preparedness, basic biomedical research and drug discovery – and even space travel.

Persistence of Long-Term Memory in Vitrified and Revived Caenorhabditis elegans. Two scientists ask the question:  “Can memory be retained after cryopreservation?” and then demonstrate that a form of long-term memory in C. elegans is not been modified by the process of vitrification or slow freezing.

06. May 2015 · Comments Off on Cryonics as a measure of rationality? · Categories: Cryonics, Society

Most cryonics advocates are often frustrated by the amount irrationality, ignorance, and hostility when other people encounter the idea of human cryopreservation. It should not be surprising then that some of us have simply concluded that most people “just don’t get it.” Which raises an important question. Is making cryonics arrangements a strong measure of rationality? After all, a close examination of Alcor members indicates that most of them are highly educated, a disproportionate number of them have PhDs, and their backgrounds are often in fields where strong analytic skills are required; computer science, neuroscience, biochemistry, etc. Another indicator is that cryonics is relatively popular in communities with a high proportion of “nerds.” In fact, a number of “leaders” in the “rationality” community (Robin Hanson, Eliezer Yudkowsky) have cryonics arrangements and have made public arguments in favor of cryonics. In short, someone who has made cryonics arrangements is not prone to short term gratification and minimizes cognitive biases, one could argue.

The problem with this characterization of cryonics as a measure of rationality is that it does not explain why the overwhelming number of people who can be considered highly analytical or rational have not made cryonics arrangements. Many cryonicists are smart but most smart people are not cryonicists. To explain this we will have to look elsewhere.

The 18th century skeptic and analytical philosopher David Hume once wrote that “reason is a slave to the passions.” In the case of cryonics, no matter how smart a person is, if the person does not have a passion for life (and an aversion to death and aging) that person will not be primed for an enthusiastic personal endorsement of cryonics. Closely related to having a desire to live and to pursue life extension is a an optimistic temperament. A cryonicist is not necessarily “wildly” optimistic, but (s)he should at least think that life is worth living and not be prone to thinking about the future in dystopian terms. I am also inclined to think that such a person is prone to think “like an economist” (to use Bryan Caplan’s phrase). With this I mean that a person can think in a probabilistic manner, does not see the world as a “zero-sum game,” and sees developments like automation, computerisation and biotechnologies in a positive light.

Do these combined traits produce a favorable attitude towards cryonics? This still cannot be the complete story because the traits discussed so far are shared by many millions of people in the world and support for cryonics is extremely small. I want to single out two additional traits that are usually required to prime someone for cryonics. The person also needs to be a non-conformist of some kind. When cryonics is as small as it is, strongly endorsing cryonics makes someone stand out (to put it mildly). And this “standing out” is not comparable to just having a bizarre hobby or a strange sense of style. It can sometimes produce confusion or hostility in other people, which can turn even our most life-affirming friends and family into apologetic pro-mortalists.

The most important trait, in my opinion, and the one that really distinguishes the cryonicist from the non-cryonicist, is the ability to deal with vulnerability, uncertainty and the unknown — in some cases, to even welcome it. People who have been around in cryonics for awhile know that ultimately (that is, when you dig a little deeper) skeptics are really afraid to be resuscitated in a distant and unknown future. This should not be easily dismissed. Personal identity is not identical to the brain or the body (as a simplistic version of cryonics would have it) but extends to all the things and people that have become part of a person’s life. To many people, the cryonics proposal means  survival at the cost of losing everything that gives meaning to their lives.

If we look at the limited acceptance of cryonics from this perspective, does this inspire optimism in persuading more people? An immediate response would be negative because fundamental character traits are hard to change. Another approach, however, is to change the conceptualization and delivery of cryonics so that these fears are not triggered. In particular, it might serve a cryonics organization well to transition from an organization that just “stores” a human body or brain without specific resuscitation and reintegration scenarios to an organization that offers more comprehensive means of identity preservation. Such an organization puts a strong emphasis on the cryopreservation of families and friends. It will offer means of asset preservation and personal belongings. It develops specific resuscitation protocols which are updated and calibrated as our knowledge and technologies improve. And it makes serious efforts to provide a reintegration program which seeks to minimize adjustment to the time in which an individual is resuscitated.

Is endorsement of cryonics a measure of rationality? Yes, but without a desire to live, a reasonably optimistic attitude, an independent mindset, and, most of all, confidence in a cryonics organization to preserve all that is important to a person, being smart by itself is not going to do it.

This is a web-exclusive edition of the Quod incepimus conficiemus column that is published in Cryonics magazine but was omitted from the April 2015 issue.

20. January 2015 · Comments Off on Alcor vs Disintegration · Categories: Cryonics, Society

This article was previously published in Cryonics Magazine, May, 2013

In this short article I will discuss two distinct developments in contemporary cryonics that are setting the stage of how cryonics is going to be practiced in the foreseeable future.

First, there is the recognition that the most formidable obstacle for people to make cryonics arrangements is not scientific or technological, but psychological. We know this because people tell us so. It is a form of anxiety about the future and social alienation that is even a concern for people who have made cryonics arrangements. Ignoring this and/or telling people to “toughen up” is simply not an effective response.

Second, there is an increasing interest in long-term wealth preservation among people who have made cryonics arrangements and this interest is no longer confined to wealthy Alcor members. In addition, there is also a growing interest in preserving biographical information, ranging from personal memories to tangible objects. This development can reflect a desire to prevent “disintegration” (see Keegan Macintosh’s excellent article in this magazine) during cryostasis or may be motivated by the use of such information for damage repair or validation of resuscitation attempts.

It seems clear to me that these two developments are closely associated and that Alcor can address the desire of their members to preserve biographical information, remain “connected” and make cryonics a less anxiety-inducing choice at the same time.

In the April 2013 issue of Cryonics magazine Mike Anzis contributed a useful review of very long-term storage alternatives for personal information and materials and all these options have their pro’s and con’s. I suspect that many people not only have reservations about the long-term survival of many of the organizations and companies reviewed, but also have concerns about privacy and the alignment of the goals of these entities and the objective of personal survival.

While it is unrealistic to expect that Alcor can be involved in all matters concerning personal data storage and reintegration (there is an argument for diversification and redundancy, too) it seems rather obvious that Alcor has a more substantial role to play than it does today. It needs to play a substantial role if we want Alcor to be perceived as an organization that does not just see reversible cryopreservation and rejuvenation as a technical problem to be solved, but one that will also do its best to give its patients a face, maintain the social integration of its patients, and facilitate means to protect personal assets and personal information.

I cannot do justice to the practical aspects of this objective in this short article but let me conclude with a number of specific suggestions.

We do not know whether email in its current format will still exist in the future but we do know that Alcor owns a domain name and can issue email addresses to their cryopreservation members and provide secure storage of email messages.

We do not need to speculate as much about the nature and compatibility of very long-term data storage technologies if Alcor starts offering such services and will ensure to upgrade them as times change. In addition, Alcor can allow its members to securely edit their personal information and medical records to allow for a better response in time of need.

Alcor can hardly compete with social networking platforms such as Facebook and Google+ but we can make an effort to offer individual members the opportunity to create a private or public online profile that will be retained after cryopreservation of the member, and that can perhaps even be updated by Alcor, family, and friends.

The benefits of such changes are greater than just offering Alcor members more opportunities to retain personal information, prevent disintegration, and more strongly identify with their cryonics organization. By giving our members a visible place and the tools to remain relevant we will also communicate to the rest of the world that we are serious and that we will not let our members slide into oblivion – even during cryostasis.

20. January 2015 · Comments Off on Cryonics and Natural Selection · Categories: Cryonics, Death, Society

“…it is not the strongest that survives; but the species that survives is the one that is able best to adapt and adjust to the changing environment in which it finds itself” so reads a quote that, in modified form, often has been mistakenly attributed to Charles Darwin but was in fact a description of Darwin’s views penned down by a Professor of Management and Marketing named Leon C. Megginson in 1963. But, surely, one reason for the popularity of this quote is that it captures the modern view of evolution quite well. In this column I would like to briefly reflect on what cryonics means in the context of evolution and natural selection.

Any cryonicist that has not kept his support of cryonics completely to himself must have found himself in a situation where even the most reasonable arguments seemed to leave someone else completely indifferent, or even hostile. Even in the case of family members or friends there comes a point where one cannot help thinking, “well, if you would rather die than think, fine, I am not going to stop you.” It appears, then, that people who make cryonics arrangements are part of an extremely small group of people that will escape the common fate of all humans (i.e. death), as a consequence of being extremely open-minded and adaptable.  But is this the “survival” that the theory of natural selection speaks of?

The modern theory of natural selection is essentially about reproduction. It is not necessarily the longest-lived species (the survivors) whose (genetic) traits will become more common in a population but the ones whose fitness leads to greater reproductive success. It can hardly be denied that cryonicists are extraordinarily capable of adapting to change (or ready to adapt to future change) but it has also been quite firmly observed that cryonicists (or life extentionists in general) are lagging the general population in terms of reproduction, either because of the higher number of single persons or because of the lower interest in having children. It is sometimes observed that whereas most people seek “immortality” by ensuring their genes will survive in future generations, cryonicists see immortality by seeking to survive themselves. In addition, even allowing for a growing interest in cryonics, the number of people making cryonics arrangements is simply too small to have a meaningful effect on the genetic and mental traits of future generations. At best, cryonicists may find themselves being perceived as independent, courageous, individuals that were simply more capable of anticipating the future of science and medicine.

It is tempting, indeed, to think of cryonicists as a homogeneous group of people who are extraordinarily analytic and adaptable but a closer inspection of the motives of people who make cryonics arrangements suggests something different. Indeed, if we look at the early days of cryonics, we see a disproportionate number of cryonicists who where extraordinary visionaries, sometimes independently arriving at the same conclusions (think of Robert Ettinger and Ev Cooper). As cryonics received more mainstream exposure, however, we see different reasons why people endorse cryonics. A partner has cryonics arrangements and the other person is persuaded to do so, too. Subcultures in which making cryonics arrangements is strongly endorsed (like transhumanism). A strong fear of death that prompts a person to do anything to not die, regardless of a dispassionate assessment of cryonics. In more recent times, even career considerations can be a factor as more “market-based” salaries are available in the field of cryonics. Still, despite the possibility that the personality type that chooses cryonics is increasingly getting more diverse, it still makes sense to talk about the demographics of cryonics for as long as the cryonics population is substantially different from the general population.

Where does all this leave us concerning cryonics and natural selection? Since natural selection is basically about reproductive success despite death it would not be correct to characterize the small group of cryonicists that will survive (where others do not) as an example of Darwinian evolution in action, I think. It may be tempting to use Darwinian terminology to characterize our situation but upon closer scrutiny there are problems with this. What might be said, though, is that (successful) cryonicists will be in the extraordinary situation to live for such a long time that they can see human evolution further unfold and even be in a position to consciously direct it through human enhancement.

This is a web-exclusive edition of the Quod incepimus conficiemus column that is published in Cryonics magazine but was omitted from the December 2014 issue.  

16. October 2014 · Comments Off on Cryonics without Repair · Categories: Cryonics

Cryonics Magazine, August, 2013

Why Reversible Cryopreservation Matters

[The following is a text adaptation of a PowerPoint presentation given on Sunday, May 12, 2013 at the Resuscitation and Reintegration of Cryonics Patients Symposium in Portland, Oregon.]

Let’s start with the following definition of cryonics:

“Cryonics is the stabilization of critically ill patients at ultra-low temperatures to allow resuscitation in the future.”

As you can see, nothing in this definition says that repair is an intrinsic feature of cryonics. But is this a reasonable perspective? Let’s think about a number of aspects of cryonics that could be classified as “repair.”

• Critically ill patients are sick and will need medical treatment in the future.
• Most cryonics patients will require
• The cryopreservation process itself causes (irreversible) damage.

Yes, cryonics patients will require a second look at their condition by a future doctor who will have more advanced medical technologies at his/her disposal. This could conceivably be called “repair.” Most cryonics patients will also require rejuvenation biotechnologies. After all, it makes little sense to cure the patient’s disease but leave him/her in a fragile, debilitated state. This could be called “repair” too, in particular if you believe that aging is the progressive accumulation of damage. The repair that I want to discuss here is repair of the damage that is associated with the cryopreservation process itself. If we can eliminate this kind of damage, and the associated requirement of repair in the future, we will make the idea of cryonics a whole lot more attractive. What would be the advantages of being able to offer such “cryonics without repair?”

Perhaps the most obvious advantage is that cryonics could not be dismissed solely by pointing to the (irreversible) damage caused by the cryopreservation process itself. In essence, such a form of cryonics would be akin to putting a critically ill patient in a state of true suspended animation. This would strengthen the legal position of cryonics patients because a decision to abandon a patient in such a condition would be more akin to murder (or at least serious neglect). Another advantage would be that the absence of cryopreservation damage would increase the likelihood of the patient being restored to good health in the future. Less damage is also likely to translate into lower costs, too, and it is rather obvious that such an advantage can mean more security for the patient. Reversible cryopreservation may also lead to earlier treatment and resuscitation attempts, which may reduce challenges associated with re-integration. Cryonics without repair also matters in the here-and-now. Without the goal of reversible cryopreservation there are no objective, empirical criteria to evaluate the quality of care in a cryonics case. Last, but not least, we should do no harm. Allowing unnecessary injury of the patient because future advanced technologies should be able to fix it is a morally suspect gamble with a person’s life.

That is an impressive list of arguments in favor of offering reversible human cryopreservation. Now let’s try to be more specific about what cryonics without repair means. Clearly, the condition of the patient should not worsen relative to the critical condition the patient was in at the time of pronouncement of legal death. In fact, a rarely recognized possibility in a good cryonics case is that it might even be feasible to slightly improve the condition of the patient through the administration of cerebroprotective medications and washing out the blood, provided these procedures do not restore spontaneous circulation and consciousness, of course. A common perspective at Alcor to look at the objective of stabilization procedures is to say that these procedures should be aimed at maintaining viability of the patient by contemporary criteria. In the past I have characterized this objective as securing viability of the brain, but I think it would be better to aim for complete viability of the body unless there is a clear trade-off between viability of the brain (the most important organ in cryonics) and the rest of the body. Ultimately, though, we do not just want to be able to reverse the stabilization procedures but all cryonics procedures.

Before we walk through basic cryonics procedures to identify obvious and notso- obvious opportunities for cryonics procedures to produce additional damage, let’s look at circumstances in which the patient suffers additional damage that cannot be attributed to the cryonics organization. The most obvious situation is where there is a long delay between pronouncement of legal death and the start of cryonics procedures because hours go by before the patient is discovered or hospital administrators do not allow immediate access. It is important to recognize that the goal of maintaining viability can be defeated before we even start our procedures. Critics of cryonics often talk about compromising circumstances as if they are intrinsic aspects of cryonics instead of the result of tragic but avoidable events or hostile authorities. Reversible cryopreservation is only possible if the cryonics organization is notified in time and receives good cooperation from hospital administrators and other authorities.

The first real opportunity for a cryonics organization to “screw up” is to allow substantial periods of warm and cold ischemia. This can happen in a number of ways including, but not limited to, not restoring adequate circulation, inadequate ventilation, allowing blood pressure and cerebral perfusion to drop (restoring blood pressure does not guarantee good cerebral blood flow), suboptimal induction of hypothermia, or conducting surgery at high temperatures without metabolic support. In ideal circumstances a cryonics stabilization is conducted so that suboptimal results in one of these areas are offset by gains in the other protocols.

If a cryonics organization is able to provide metabolic support and rapidly cool down the patient to close to the freezing point of water the next challenges involve the cryopreservation process. The best known form of damage here is, of course, ice damage. While today’s vitrification agents are formulated to inhibit ice formation at realistic cooling rates, there are still a number of things that can go wrong. The distribution of cryoprotectant in the brain can be incomplete as a result of surgical errors or flaws during cryoprotective perfusion (e.g., vessels not properly cannulated, extremely low or high pressures, pumping air, etc.) The cryoprotectant can also be introduced at temperatures that are too warm or introduced too rapidly to allow the cells to maintain volume in an acceptable range. Even if none of these mistakes are made, we run into other challenges that cryonics organizations cannot successfully overcome yet.

Successful vitrification requires the use of high concentrations of organic solutes (such as DMSO and formamide) and non-penetrating polymers. While much progress has been made by cryobiology researchers Gregory Fahy and Brian Wowk to formulate solutions with low toxicity, and such solutions have been shown to successfully cryopreserve brain slices, our current understanding is that it is not likely that the brain of a cryonics patient remains spontaneously viable after being equilibrated with these agents. This is partly because the “blood brain barrier” leads to a situation in which solutes naturally present in the brain become concentrated during cryoprotective perfusion (dehydration) as discussed in the next paragraph. This causes cells inside whole brains to be cryoprotected by a mixture of natural solutes and some components of the perfused cryoprotectant solution rather than just the carefully-formulated cryoprotectant solution. Sometimes natural is not good.

It is sometimes said that eliminating cryoprotectant toxicity is the “holy grail” of cryonics research. While there is good empirical evidence to suggest that despite this toxicity good ultrastructure of the brain is still possible, true reversible human cryopreservation without reliance on sophisticated repair will require cryoprotectants with much lower toxicity. The need for less toxic cryoprotectants is especially tied into the problem of achieving concurrent and adequate distribution of cryoprotectant to all parts of the body that are vulnerable to freezing injury, which requires many hours of perfusion. In addition to cryoprotectant toxicity there are a number of other poorly-understood phenomena that could frustrate the ideal of cryonics without repair such as “chilling injury” and “thermal shock.”

An interesting form of injury that is not well known by the general public but that triggers a lot of discussion among cryonics researchers is dehydration of the brain. Without exception, a wellconducted cryopreservation of the brain with present technology produces severe shrinking. In fact, this shrinkage, and the corresponding increase in concentration of salts and proteins naturally present in the brain, appears to be a key mechanism by which whole brains vitrify despite limited permeability to perfused cryoprotectants. Evidence of substantial dehydration (obtainable by direct inspection of the brain inside the skull or via CT scans) is often considered an indicator of good care in cryonics. Of course, this leaves the question unanswered whether such a degree of dehydration is compatible with viability of the brain. Yuri Pichugin, the researcher who developed the Cryonics Institute’s current vitrification agent, VM-1, considered such extreme cerebral dehydration an obstacle to restoring viability after vitrification and identified a number of blood brain barrier modifiers that allowed him to recover brain slices after whole brain cryoprotective perfusion with improved viability. Whether such agents are of benefit or actually harmful is still an open research question.

Even if we could cryopreserve a human being without ice formation, toxicity, chilling injury, or other forms of injury associated with cryoprotection, there is still one remaining obstacle for reversible  cryopreservation: fracturing caused by thermal stress. While fracturing has been recognized as a problem and observed as an empirical phenomenon in patients as far back as the early 1980s, this form of injury has pushed itself to center stage (together with cryoprotectant toxicity and cerebral dehydration) since cryonics organizations started using vitrification agents aimed at eliminating ice formation altogether. If ice formation is eliminated, fracturing is the only mechanical form of damage left. While the significance of fracturing damage is sometimes downplayed by molecular nanotechnology experts, and fracturing at cryogenic temperatures doesn’t result in actual fragmentation, letting a human brain form fractures is not what most people would consider appropriate treatment of a critically ill patient.

What is striking, however, is how little we actually know about fracturing in cryonics patients. Fracturing has been observed in patients that were cryopreserved with (relatively) low concentrations of cryoprotectants. Such protocols produced ice formation and we should therefore not be surprised about observing cracking in those patients. Even in patients who have been cryopreserved using modern vitrification agents acoustic fracturing events (which may or may not correspond with actual fractures) have been detected above the glass transition temperature (Tg) of the pure vitrification solution. But even these observations have little relevance to the question of what we should expect in a good case. Many cryonics patients are perfused under sub-optimal conditions due to delays after clinical death. It is therefore likely that many of these fracturing events, if real, can be attributed to ischemia-induced perfusion impairment and ice formation. And that cooling frozen tissues to very low temperatures can cause fracturing is something we already know.

There are some encouraging preliminary research results suggesting that under ideal circumstances (i.e., good equilibration, controlled cooling) fracturing is not as serious a problem as it has been made out to be. The current practice of long term care at liquid nitrogen temperature may not be salvaged by such observations, but the intermediate temperature storage (ITS) systems that have been developed might be sufficient to eliminate this problem under good conditions at temperatures not too far below Tg. A related intriguing question is what the effect of severe cerebral dehydration is on the occurrence and frequency of fractures in the brain.

Let’s say that one agrees with the objective of “cryonics without repair” (or very limited repair), and the identification of the biggest scientific and technical obstacles to achieve this. What should our research and clinical objectives be? For starters, cryonics organizations should continue to cultivate an interest in personal alarm systems and securing good legal and logistical cooperation with providers of medical care. One technical development that deserves to be introduced is “field vitrification.” Strictly speaking, the phrase is a misnomer because we are not really talking about the patient being vitrified in a remote location; it is the cryoprotective perfusion part of the procedure that is done prior to transport to Alcor (in remote cases). Evidence from at least three labs indicates that perfusing the patient in the field with a vitrification solution and shipping on dry ice is safe, practical, and superior to blood substitution in most scenarios. While remote blood substitution (“washout”) is clearly demonstrated to be better than shipping the patient without removing the blood, it is not likely that hypothermic organ preservation solutions capable of keeping the brain viable for longer than 24 hours, and capable of inhibiting whole body edema, will be developed any time soon. Field vitrification is simply the next logical development in high-quality evidence-based cryonics. Other important improvements include better cooling efficiency (e.g., using cyclic cold lung lavage), improved cardiopulmonary support protocols, a renewed emphasis on monitoring during casework, and the introduction of intermediate temperature storage.

The most formidable challenge will be to develop what I call “brain-friendly” cryoprotectants. What needs to be accomplished? These agents should have no, or tolerable, toxicity, eliminate chilling injury and other poorly-understood forms of cryopreservation injury, allow safe and fracture-free storage at intermediate temperatures, and allow cryoprotective perfusion with greater penetration of agents into brain tissue with less dehydration so that results in whole brains can more closely match the high viabilities now obtainable in brain slices.

At my own company, Advanced Neural Biosciences, we have successfully developed a rat EEG model to screen for such brain-friendly cryoprotectants. As I write up this presentation, we have been successful in recovering integrated whole brain electrical activity after hypothermic circulatory arrest at 0° Celsius. Our next objectives are to recover EEG activity in the brain after cooling to subzero temperatures and to understand the relationship between cryoprotectants, the blood brain barrier, dehydration, and viability. It is too early to report any significant findings yet, but one thing that has become quite clear to us is that adequate ventilation during cool down is essential to recovery of whole brain activity. This is rather important because cryonics organizations have not been that concerned about meeting the brain’s demand for oxygen during stabilization, and during blood washout and blood substitution in particular. No doubt, if we continue this research we will learn other things that have direct relevance to the practice of cryonics.

The whole brain cryopreservation research project has been made possible by the generous support of the Life Extension Foundation. The author also wishes to thank the Immortalist Society, Cryonics Institute, Alcor, LongeCity, 21st Century Medicine, Alan Mole, York Porter, Jordan Sparks, David Ettinger, Ben Best, Mark Plus, Peter Gouras, James Clement, Luke Parrish, and John Bull for additional support.

13. October 2014 · Comments Off on Can You Build a Locomotive out of Helium? · Categories: Cryonics, Neuroscience, Science

First published in Cryonics, 4th Quarter 2011

Robert Ettinger on Substrate-Independent Minds

Introduction and Afterword by Aschwin de Wolf


Robert Ettinger, the “father of cryonics,” was cryopreserved on July 23, 2011. While Ettinger’s book Man into Superman (1972) is considered an important contribution to transhumanism, he increasingly came to recognize that most people do not desire a hard break with the past and resist radical transformation. During the last years of his life he became a vocal critic of ‘mind uploading’ as a means of personal survival and spent a considerable amount of time refining his arguments why mind uploading is not likely to work. This document organizes excerpts from his last book Youniverse and mailing list messages on the topic of substrate-independent minds. In the afterword, I make a brief attempt to place his contributions in a broader philosophical context.

The title of this document refers to a message that Robert Ettinger sent to the Cryonics Institute mailing list on July 21, 2011. In response to the claim that the human mind is a machine, and that the function of any machine can be duplicated by a machine built of another material, Ettinger asked, “Can you build a locomotive out of helium?”

Mind Uploading

“A large and burgeoning group of scientists, including some of the brightest, believe that—in principle—computers will fairly soon be able to think in the fullest sense of the word. They will be living, conscious entities with feelings and subjective experiences.

“A corollary—many believe—is that your persona could be uploaded into a computer and you could then live an incomparably bigger and better life as a simulation or emulation.

“I think the uploading thesis is probably wrong, although (as usual) it’s too soon to be sure. But the issue is a significant part of modern philosophy, and potentially has enormous practical importance.

“…I am among the radicals in the expectations for AI. But intelligence is not life. It is by no means proven that life as we know it with subjective experience can exist on an arbitrary substrate, such as silicon.” (Youniverse)


“One extreme school of thought holds that information and its processing constitute everything that is important. In particular, you are essentially just a collection of information, including a program for processing that information. Your ‘hardware’—the nervous tissue that embodies and handles the information—is only secondary.

“My conclusion will be that it is not necessarily possible—even in principle—for consciousness to exist on an inorganic substrate, and in fact that it is unlikely.

“Sometimes the doubters are accused of dualism—the increasingly discredited belief that the living and inanimate worlds, or the material and the spiritual worlds, are separate.

“This certainly is not true of me or of many others who question the information paradigm. I am a thoroughgoing materialist and reductionist. I will not feel in the least dehumanized if it turns out the information paradigm is right…I have strong doubts, but they are based entirely on the evidence, or lack thereof.

“The most radical of the ‘strong AI’ people believe that all thinking is information processing, and all information processing is thinking; and they appear to believe that consciousness is just an expression of complexity in thinking.

“People who talk this way must be admired for boldness and strength of conviction, but I think not for clarity of thought.

“The point is, all physical phenomena, all interactions, involve information processing in some sense. But that isn’t all they do. A computer, or a person with pencil and paper, could figure out—describe or predict—what the atoms do, and that would be an analog of the information processing part of the phenomenon; but only the actual, physical atoms can form an oxygen molecule. And to anthropomorphize or analogize ‘feelings’ and ‘thoughts’ into these phenomena is simply unjustified. It amounts to declaring, by fiat, that thinking and feeling are inherent in information processing; but saying so doesn’t make it so.” (Youniverse)

Turing Tests and Zombies

“Alan Turing was a brilliant mathematician and computer pioneer. He played an extraordinary part in winning World War II through his work in cryptography for British Intelligence. He also showed many of the potential capabilities of general computers. But one of the works for which he is most famous is badly flawed or has been badly misused—the ‘Turing test’ for intelligence/- consciousness.

“Again, I am a firm materialist and reductionist: I readily concede the possibility that a machine could (conceivably) have life and consciousness. But I deny that we can assume that (inorganic) machines have this potential; and with still more help from Turing I think I can make the case persuasive.

“‘Uploaders’ or ‘upmorphists’ or patternists generally maintain that our identity resides in our information content. Their most extreme position is patently absurd—that ‘we’ literally persist, in some degree, if any of the information about us is preserved, even our writings or biographical data. (Shades of Woody Allen! ‘I don’t want to live on in my works; I want to live on in my apartment.’) Anyone who believes this needs more help than I can provide.

“Turing ingeniously showed that a strip of paper tape marked in squares, with zeroes or ones marked on the squares according to certain rules, along with a simple mechanism for moving the tape and making or erasing marks, could be a universal information processor—i.e., it could accomplish any information processing task that any digital computer (serial or parallel) could do, given enough time. It could even produce any result that a quantum computer might, albeit at a teeny-tiny fraction of the speed.

“You certainly can’t claim that a paper tape (even when it is moving) is alive or conscious! Yet that tape, in theory, could produce any response that a person could to a particular stimulus—if by ‘response’ we mean a signal sent to the outside world, suitably coded. It could converse with perfect fidelity to an individual’s character, and over a teletype could fool that person’s husband or wife.

“My original objection to the uploading assumption was simply that we don’t know anything about consciousness or feeling, hence it is premature to assume that it can exist other than where we know it exists, viz., in organic brains. It is entirely possible that meat machines (as opposed to machines of silicon or metal etc.) have some unique quality that allows the emergence of feeling and consciousness. Until we can isolate and define the mechanisms of feeling—of the subjective condition—we must reserve judgment as to the possibility of inorganic people. (Youniverse)

“Uploaders tend to put faith in the Turing Test  for human intelligence, and to believe that zombies cannot exist. Let’s  take a quick look.

“Communicating (say) by email, a testor tries to determine whether the testee is a human or a computer program. Passing the test supposedly proves the  testee is human or equivalent. But the test is clearly worthless, since it  produces both false positives and false negatives. As much as 50 years  ago Eliza, a program pretending to be a psychiatrist, fooled many people—false positives. And of course a child or a retarded person could perform below par and produce a false negative. The Turing test is baloney.

“In similar vein, uploaders tend to believe that something which outwardly behaves like a person must be a person. They reject the possibility of zombies, systems that by their actions appear to be sentient but are not. Yet it  is often easy to fool people, and, as already noted, programs have fooled  people even though no one claims the programs were alive.” (Cryonics Institute Mailing List, September 9, 2010).”

Imperfect Simulations

“..any simulation created in the foreseeable future will be imperfect, because it will necessarily reflect current theories of physics, and these are known to be incomplete and almost certainly in error to some extent or in some domains. Whether this would necessarily result in material deviations of the simulation from the course of nature, and in particular whether it would preclude feeling, we don’t yet know. But we do know that the simulation would be wrong, which in itself is enough to justify withholding judgment on the possibility of living computers.” (Youniverse)

Analog Failures

“The uploading thesis depends on the assumption that any organic process in the brain can be duplicated by analog in some other medium but this not only isn’t obvious; it’s nonsense.

“For example, suppose a certain process depends on magnetism, and all you have to work with are the mechanical forces transmitted by rigid bodies. Can you make an electric motor out of tinker toys? Can you build a synchrotron out of wooden boards and nails? Uploaders think a computer (of the electronic variety) can be a person: how about a Babbage mechanical computer made of rods and gears? Presumably, any kind of information processing and storage can be done by a collection of rods and gears but could rods and gears conceivably be conscious? I doubt it; not all media are created equal. So it is entirely possible that organic brains have potentialities not realizable anywhere else in the universe.” (Youniverse)

“Just ask yourself what consciousness is—what physical condition or process constitutes consciousness. You don’t know, hence you cannot know that a simulation  fills the bill.” (Cryonics Institute Mailing List, September 16, 2010)

Petitio Principii

“It seems to me that all the computer-metaphor people… keep making the same error over and over again—assuming as a premise the very hypothesis they are trying to establish. When the premise is the same as the conclusion, naturally the conclusion follows from the premise. They refer repeatedly to ‘all computational devices’ etc., implying that the brain is just that—another computational device—when in fact that is precisely what is at issue: Is the brain possibly something more than a computational device? The computer metaphor is plausible (and I am not in the least uncomfortable with it) but plausibility isn’t proof.” (Youniverse)

The Map is not the Territory

“Adherents of the ‘information paradigm,’ I believe, are deceived in part by glibness about  ‘information’ and hasty ways of looking at it.

“Apprently it needs to be said again and again: a description of a thing or a process—no matter how accurate and how nearly complete—is not the same as the thing or the process itself. To assume that isomorphism is enough is just that—an assumption, not self-evidently permissible.

“Even though (for example) a computer program can in principle describe or predict the behavior of a water molecule in virtually all circumstances, a water molecule for most purposes cannot be replaced by its description or program. If you pile up 6.02 x 1023 computers with their programs, you will not have 18 grams of water, and you will have a hard time drinking it or watering your plants.” (Youniverse)

“Eliezer Yudkowsky (and other uploaders) claim that mapping a system results in a map that effectively has the same properties as the original. Well, look again at one of my counter-examples. I write down with pencil and paper the quantum description of a hydrogen atom in its ground state. It could hardly be more obvious that the marks on paper do not constitute a hydrogen atom. And if you put side by side two papers describing two hydrogen atoms, they will not combine to form a hydrogen molecule. In principle, of course (the math is difficult) you could write down expressions corresponding to the formation of hydrogen molecules from hydrogen atoms, but you will still have just marks on paper.

Once more, a simulation is just a coded description of a thing, not the thing itself.” (Cryonics Institute Mailing List, September 18, 2010)


“The term ‘identical’ is used in different ways by different people. To  some, two systems are identical if they differ only in location, e.g. two  hydrogen atoms in ground state. But I have pointed out that a difference in location necessarily implies other differences as well, such as gravitational fields. Hence my position is that, if the question arises, are A and B  identical, then they are not.

“If two systems differ in spatial or temporal location, then they may be identical to most observers for most purposes, but survival of one does not  imply survival of the other. Suppose you, as you are now according to local  observation, also exist at a great distance in space or time (either past or  future), just by accident. I see no reason for the survival of B to imply the survival of A.” (Cryonics Institute Mailing List, September 16, 2010)


Robert Ettinger presented a number of distinct arguments (no fewer than fifteen, by his own count!) against mind uploading and I cannot pretend to have presented them all in this document. I think there are a number of core positions associated with Ettinger’s argument that can be stated quite succinctly, however.

  1. Whether mind uploading is possible is ultimately an empirical question and cannot be settled conclusively by analogies or thought experiments.
  2. A description of a material object is not necessarily the same as the object.
  3. A simulation must be erroneous because the program necessarily is based on our incomplete knowledge about physics.
  4. Consciousness may be substrate-dependent.
  5. A copy of a person may not constitute personal survival.

The common denominator that runs through Ettinger’s critique of substrate-independent minds is a thorough empiricism about knowledge. Ettinger does not categorically rule out the feasibility of mind uploading but takes people to task for dogmatic claims on these topics in absence of empirical corroboration.

Ettinger was particularly irritated by the claim that materialism commits a person to the acceptance of mind uploading. He could not see how a rejection of the soul excludes the view that certain materials are uniquely suitable, or even exclusively suitable, for a certain function. One might add that it is even conceivable that the mind is substrate-independent but that existing organic chemistry provides the most versatile basis for advanced consciousness and survival.

Most of the issues that Ettinger was concerned about may be resolved by the time he will be resuscitated but it is possible that some of the issues that are at stake in this debate are ultimately un-falsifiable or even pseudo-problems. For example, how could we settle the question of whether a copy is “really you?” Obviously, a copy of something will always confirm that (s)he is really him- or herself but that is of little help in resolving the question. Similarly, we may never be able to conclusively verify (or falsify) that a computer has consciousness or feelings. Is it even conceivable that new super-intelligent life forms will replace humans without being conscious or having feelings! Evolution selects for fitness, and whether this implies consciousness is an open question.

So who is right, Robert Ettinger or his critics? I think what captures Ettinger’s perspective the best is to say that if you expect an answer right now, you have not paid close attention to his argument.

04. October 2014 · Comments Off on Connectome: How the Brain’s Wiring Makes Us Who We Are · Categories: Cryonics, Neuroscience, Science

Connectome: How the Brain’s Wiring Makes Us Who We Are by Sebastian Seung, Houghton Mifflin Harcourt Trade, 384 pages, 2012.

[This review originally appeared in Venturist News and Views, June-July 2012, 6-7 and Cryonics, September-October 2012]

The scientific perspective that informs Sebastian Seung’s bestselling popular neuroscience book Connectome is so familiar to cryonicists that the bulk of this book could be mistaken for an extensive introduction to the philosophy of mind embodied in cryonics. His book offers a rigorous exposition of the view that our identity is encoded in the connections between neurons, the “connectome,” which itself is shaped by our genes and life experience. The strength of this book is not only its review of the empirical evidence that supports this outlook but its encouraging the reader to think about its implications.  Readers who are intimately familiar with the argument in favor of cryonics should not assume that there is little to learn from this book. As imaging and storage technologies evolve, cryonicists can do more now than in the past to learn about their individual connectome, strengthening the likelihood of successful resuscitation.

One important element of the connectionist premise that structures Seung’s book is that it does not completely resolve competing theories about how the brain works. For example, the recognition that long-term memory (and identity) does not depend on transient electrical activity but has a more robust long-term physical basis that persists during cessation of brain activity (examples are hypothermic circulatory arrest and short periods of cardiac arrest) does not imply a single perspective on how the genome provides the neurological bases for memory formation, retention, recollection, and re-prioritization. One interesting perspective, “neural Darwinism,” which was anticipated by the multi-talented classical-liberal economist Friedrich Hayek, proposes a theory of brain function in which a genetically determined wiring of the brain is subject to competing experiences that strengthen or weaken populations of synapses throughout life. One of the interesting implications of this theory is that consciousness can be treated as an emergent outcome of micro-events in the brain, instead of a mysterious, autonomous property of the brain (think of the curious concept of “free will”).

Seung devotes two chapters to the nature-nurture debate through a connectionist perspective. One of the unfortunate effects of the nature-nurture distinction is that it masks the obvious point that what we call “nurture” (upbringing, environment, etc.) is not exempt from biology but simply concerns the relationship between biological systems and between a biological system and its physical environment. Social scientists who have a strong “nurture”-bias should therefore not be exempted from describing “nurture” in verifiable physical terms, something that many of them do not feel the slightest obligation to do. Another unattractive feature of this debate is that it is routinely portrayed as one between genetic determinists and “environmentalists.” In reality, the debate is mostly between serious scholars who acknowledge that behavior and learning are shaped by both genetics and the environment and those who basically consider the mind a blank slate—a position that is clearly contradicted by existing science but remains popular as a premise in contemporary public policy and certain political ideologies. One of the interesting topics that Seung discusses in these chapters is whether the plasticity of the brain changes over time.

From the perspective of cryonics, the relationship between the genome and the connectome is of great importance. If some of the basic wiring of the brain that encodes personality and temperament is determined by genes and is fixed (or mostly fixed) at an early age, then some parts of the connectome might be inferred from a person’s genome, which opens up an exciting research program for cryonics. A systematic study of the field where genetics meets neurodevelopment might help in understanding the relationship between the genome and brain ultrastructure. This in turn could assist in future resuscitation attempts. To date, the assumption in cryonics has been that the complete ultrastructure of the patient must be preserved (or at least preserved in such a manner that it can be inferred), but if some of it can be inferred from the genome the repair requirements for resuscitation of cryonics patients may be relaxed. Looking for such invariable features in variable brains is an important element of a credible cryonics resuscitation research program.

The power of comparing connectomes is also recognized by Seung in a separate chapter (“Comparing”). There he reviews technologies and approaches to compare connectomes with the goal of understanding personality differences and understanding neuropathologies or “connectopathies.” This chapter is one of several in which the author reviews the existing and emerging technologies that are enabling us to produce a complete connectome, including the innovative equipment of cryonicist and Alcor member Kenneth Hayworth to perform serial electron microscopy. Also discussed are technologies such as diffusion MRI (dMRI), which allows for non-invasive mapping of the connectome at the macro scale using water as a probe. This technology may not be adequate to map the connectome at the cellular level but its contribution to comparative connectomics has already been recognized. It may also hold promise as a means to collect identity-critical information about an individual while alive, which again may lessen the computational challenges involved in cryonics resuscitation. One of the exciting prospects of the field of connectomics is that it can contribute to a further narrowing of the challenges involved in restoring cryonics patients to good health.

Seung closes his chapters on emerging technologies with a review of the prospects of connectomics for the treatment of neurological diseases. One of the potential treatments involves the re-programming of a person’s own (skin) cells to neurons, which can then be introduced in the brain to treat a disease or enhance brain function. Such an approach may also be used to fill the “missing gaps” in the brain of a cryonics patient (alternative technologies include molecular construction of neurons by advanced molecular nanotech­nology).

At this point, I think we can foresee a rather optimistic future for cryonics research and the prospect of resuscitation. Instead of conceptualizing cryonics as the preservation of clinically dead people in the hope that future medicine can restore these people to good health, we can envision a more complex, but more encouraging, path. The work of resuscitation and restoring identity is not something that is expected to occur exclusively in the future but rather will be an ongoing process that starts as soon as the patient is cryopreserved. And with the rise of advanced genomics and non-destructive imaging technologies, some of the initial work can be done while the person is still alive. One of the exciting aspects of being a cryonicist today is that you can take proactive steps to learn about your own connectome and other identity-relevant information.

Seung devotes no less than a whole chapter to human cryopreservation (and the associated idea of chemopreservation). The author recognizes that his own views about the connectome are so similar to the philosophy of mind that underpins cryonics that he needs to do some justice to the rationale of cryonics. One unfortunate aspect is that he situates his discussion of cryonics in the context of religion and immortality. It is undeniable that some cryonicists are motivated by visions of personal immortality but this idea is not intrinsic to cryonics (neither is mind uploading or transhumanism.) Properly conceived, cryonics is an experimental medical procedure that aims to stabilize patients at cryogenic temperatures in anticipation of future treatment. What really distinguishes cryonics from mainstream medicine is not uncertainty (which is a fact of life), but the temporal separation of stabilization and treatment. One regrettable implication of attributing religious motives to people who make cryonics arrangements is that it cheapens the use of the word ‘religious.’ Instead of referring to worship of a higher being, it is here used as a strong belief in something in the absence of conclusive evidence. But by putting the bar so low, Seung (unintentionally) classifies many aspects of life, including choosing novel experimental treatments in mainstream medicine, as “religious.”

At one point Seung writes that research aimed at demonstrating that contemporary vitrification technologies can preserve the connectome will “finally bring some science to Ettinger’s wager.” This is a remarkable statement because even the earliest arguments in favor of cryonics were never presented in the form of a pure wager. In his book The Prospect of Immortality, Robert Ettinger reviews existing evidence from cryobiology and neuroscience and argues that, combined with the expectation that medicine will continue to evolve, the choice to be cryopreserved is a rational decision. Since Ettinger’s book cryonics organizations and wealthy donors have expended a lot of money and time in perfecting preservation techniques and looking at the effects of new technologies on the structure and viability of the brain.  Compared to the state of, let’s say, interventive biogerontology, the scientific progress that has been made in cryonics is not trivial. For example, it is doubtful whether the widespread adoption of vitrification in mainstream cryobiology would have been possible without sustained research into using this approach for complex organs by cryonics supporters. To my knowledge, cryonicists have always been quite eager to generate experimental knowledge to inform their decision making. Now that more advanced technologies to map the human brain are becoming available, cryonics organizations are eager to use them instead of just passively maintaining their “faith.”

Ultimately, Seung still fails to recognize that cryonics inherently involves an element of uncertainty that cannot be eliminated without it not being cryonics anymore (i.e., elimination of uncertainty makes it suspended animation). For example, the author recognizes that it is not necessary for a preservation technology to perfectly preserve the connectome as long as it remains possible to infer the original state (or missing information) from what has been preserved. We can speculate what the limits of such “neural archeology” will be, but I do not think anyone can make conclusive arguments. In this sense, cryonics cannot be completely moved from the realm of informed decision making into the realm of indisputable fact. An element of uncertainty will always be associated with it, even if the experimental evidence in favor of this medical procedure keeps mounting.

The author also discusses alternative preservation approaches such as chemical fixation and plastination. One major disadvantage of existing chemical preservation technologies is that they are irreversible by contemporary techniques (literally a “dead end”) and they do not allow for viability assays to distinguish between worse and better preservation techniques. In contrast, in cryobiology, evidence of good ultrastructural preservation is often a starting point (or independent corroboration) to identify cryoprotectants that are able to store complex organs at cryogenic temperatures and restore them without loss of viability. There is one other formidable challenge that will inevitably arise if chemical preservation is offered as a means of personal survival. It is how to deal with the fact that if chemical fixation is delayed perfusion impairment will prevent complete cross-linking of biomolecules. Even more so than cryonics, chemopreservation requires that the procedure be started prior to, or immediately following, circulatory arrest. In absence of this, the fate of a person’s connectome is uncertain, and may even worsen during storage—a problem cryonics is exempt from.

The book ends with a chapter about mind uploading. One misconception about cryonics is that people seek it as a means to mind uploading, or that reviving the person in a computer is the aim of cryonics. In fact, the late Robert Ettinger became a vocal critic of mind uploading in his final years. He offered a lot of arguments for his skepticism but his main concern was that questions about the feasibility of mind uploading are ultimately empirical questions which cannot be settled by deductive reasoning and dogmatic claims about the nature of the mind or consciousness. One of the amusing aspects of the debate about mind uploading is that proponents and skeptics both accuse the other of not being consistent materialists. Interestingly enough, Seung makes an observation relevant to this debate when he writes how the idea that “information is the new soul” is implied in the mind uploading project.

Despite some misgivings about how Seung presents and conceptualizes cryonics, I am unaware of another book that offers such a clear exposition of the relationship between brain and identity that informs human cryopreservation (and chemopreservation). The most rewarding thing for me was a stronger recognition that the idea of the connectome is not just a premise but opens the door to multiple fruitful research programs aimed at personal survival.

About the Author: Sebastian Seung is Professor of Computational Neuroscience and Physics at MIT and Investigator at the Howard Hughes Medical Institute. He has made important advances in artificial intelligence and neuroscience. His research has been published in leading scientific journals and also featured in the New York Times, Technology Review, and the Economist. (From the dust jacket.)

Dr. Seung was also a speaker at the Alcor-40 conference in October 2012

08. September 2014 · Comments Off on Social Benefits of Rejuvenation Bioechnologies · Categories: Health, Society

When advocates of radical life extension discuss the social benefits of humans having much longer lifespans, it is often just a footnote to a personal desire to prolong life. As a consequence, cynicism from critics is often encountered. It hard to counter such skepticism effectively because people may believe you are just trying to make an essentially selfish desire look socially desirable.

There is an alternative. We can approach the topic from the other direction if we ask what kind of lifespans would be desirable if we want to increase social welfare and reduce human suffering. Let’s look at a number of issues.

There is a large literature about coping with the death of loved ones, relatives, and friends. While many people find support from such self-help books, most people would agree that no amount of anticipation or coping can eliminate the suffering and devastation that follows the death of a loved one. Is there an upside? I am not aware of any serious writer pontificating about the positive aspects about a person dear to you dying or suffering from aging-related disabilities. A society in which humans have control over the aging process would be desirable because it would eliminate the dominant cause of death (age-associated diseases) and the suffering it brings to survivors.

It is not uncommon to hear people being accused of not caring about the effects of their actions on future generations. This complaint is particularly prominent in discussions about the environment and the use of natural resources. If humans were not born to die on a predictable schedule this whole dynamic would change because the distinction between current and future generations would cease to exist. If consideration of the long-term consequences of our actions requires a prominent place in human life, we should not want humans to replace each other but generations to coexist in time and space.

Age discrimination involves discrimination of individuals on the basis of their age. In most instances, however, this discrimination concerns biological age and its effects on appearance, physical health, and mental skills. Biological age is not hard to observe and can usually be inferred from chronological age. If we prefer that people are not treated differently because of their date of birth we should want to live in a society where rejuvenation biotechnologies sever the link between chronological age and biological age.

What about economic welfare? Ageless people would be able to remain productive and generous, medical costs associated with the debilitating health and mental effects of biological aging would be substantially reduced, and highly talented people would not cease to exist.

Reasoning backwards from what morality and welfare would “dictate” about human lifespans is not just a talking point in discussions about the bioethics of life extension. One can imagine the rise of a social movement that seeks to educate the general public about the social benefits of biological control over the aging process. Such a social movement would not be in the business of making excuses for eccentric individual desires but would recommend that the reduction of suffering, sustainable growth, and more virtuous conduct would require that humans do not have a fixed expiration date.

Originally published as a column (Quod incepimus conficiemus) in Cryonics magazine, December, 2013