Cryonics, July 1990


by Micheal B. O'Neal


This article presents several reasons for preferring whole body suspensions over neurosuspensions. For those of you who are new to cryonics, a whole body suspension, as the name implies, involves the perfusion and long term storage of the entire patient. Neurosuspensions are similar to whole body, with the exception that only the patient's brain (encased within the cranium) is placed in long term storage.

The intent of this article is not to dispute the validity of neurosuspensions or to object to the Alcor policy of emergency conversion to the neuro option under dire circumstances. I believe a neuro-suspension is certainly preferable to no suspension at all and I fully support Alcor's policy of a conversion to neurosuspension in emergency situations.

I am disturbed, however, by the ease with which many Alcor members seem to reach the conclusion that a full body suspension is simply a waste of liquid nitrogen. According to a recent Cryonics article, about 2/3 of Alcor members have chosen the neuro option [1]. Even allowing for the economics of the situation, I find this figure surprisingly high.

Each of us must decide for ourself whether the additional cost of a full body suspension is justified by the perceived benefits. Any informed decision can only be made after careful consideration of the benefits and costs of each option. The Alcor publication: "Neuropreservation: Advantages and Disadvantages" [2] attempts to do just this. That article, however, seems to be unfairly biased in favor of the neuro option. As evidence of this conclusion I would point out that of the 17 paragraphs in the document only 4 seem to present advantages of the whole body approach (paragraphs: 1, 9, 14, 17). To be fair, articles have appeared in this and other publications [3] which favor the whole body approach. Even Mike Darwin's excellent pro-neurosuspension article, "But What Will the Neighbors Think?!" [4], devotes substantial space to a balanced treatment of the questions surrounding neurosuspension.

Many of the arguments favoring whole body suspensions over neurosuspensions have been based on aesthetic and social reasons. While these arguments are certainly valid, I do not wish to repeat them here. Instead, I would like to propose two additional technical arguments for favoring whole body suspensions.

Arguments for Whole Body Suspension

First, in my opinion, it is by no means clear that the body does not contain information critical to the revival of the person. I do not mean by this statement that I reject the fact that the human brain holds a person's mind and personality. What I do mean is that reconstruction of the person may be very difficult, or impossible, without the body.

Most everyone agrees that DNA does not completely specify a person. The argument of those who have selected neurosuspension seems to be that DNA plus the information contained in the brain does completely specify the person. I argue that we can not be sure of this.

Why? Let us consider the case of identical twins. Since they developed from the same original cell, their DNA sequences should be identical. However, twins are not exactly the same. For example, they are not always the same height and they do not have the same fingerprints. Some of these differences, such as height, may be directly attributed to environmental factors such as nutrition and health care. Other characteristics, such as fingerprints, seem less related to environmental factors and suggest that DNA programming may only specify general patterns, with the specifics arrived at in some other, seemingly random, fashion. Regardless of how these differences arise, it should be clear that a person's physical characteristics can not be fully determined from DNA alone.

So, "what is the point," you might ask. "Surely all of my memories plus an almost identical body would still be me." Perhaps. But what if the details of the central nervous system are not specified in the DNA programming?

The typical scenario for reviving a person suspended using today's primitive technology involves reconstructing a person using cell by cell (or molecule by molecule) repair techniques. If whole body procedures were used, the person's entire central nervous system would be preserved. This preservation would not be perfect. There would be damage, perhaps even fractures to the spinal cord. It has been suggested [2, page 3] that because of the likelihood of these fractures there is little reason to prefer a whole body suspension. I would like to point out that repair of a damaged system, even a spinal cord, is likely to be much less complex, and more accurate to the original, than an unguided reconstruction based on DNA.

This leads me to conclude that without the original body to serve as a guide, it may not be possible to "interface" the neuropatient to a [re-grown] body. Even if an approximation of the original connections can be designed, the new body may not "feel" right due to the subtle differences that are sure to exist between the original body and [a re-grown one].

My second point is that even if revival is possible without a complete body, the existence of the body may make revival easier and help reduce personality and memory loss caused by a less than perfect suspension.

The physical characteristics of our bodies strongly influence who we are. Our actions also strongly influence the condition of our bodies. Hence, we can think of our bodies as a crude physical backup for personality and memory.

Many people in the cryonics movement have pointed out the need to keep records and memorabilia to backup crucial memories. While this is certainly a good idea, it should be pointed out that information of this type cannot entirely replace the information stored in our bodies, since there is always the chance that our bodies contain important information that we are unaware of.

An examination of a well-preserved body can tell an expert much about that person. Present-day anthropologists are able to determine many details of a person's life from an examination of a (poorly preserved) body together with clothing and jewelry. Details such as overall medical condition, age at death, even social standing and, perhaps, occupation can be determined. The person may not have been aware of some of these details, such as an undiagnosed medical condition, even if the impact on his life was great.

One could argue that in the vast majority of cases most information available from an examination of the body would be known to the person and therefore be available in the suspendee's brain. Even if some memories are apparently destroyed by a poor suspension, many traces of them may remain. Surely, during patient reconstruction, these partial memories will be discovered and enhanced.

This argument overlooks the very real possibility that a patient's brain may be repaired without an understanding of the personality and memory information it holds. This is a very important point. Reconstruction and repair of a brain does not imply access to the memories it contains.

Perhaps the best way to understand why this is true is to look at "neural net" computers. The connectionist machine or neural net is composed of a large number of simple processing elements that are highly interconnected. Each of these elements is modeled after biological neurons, the basic components of the human brain. Information in such systems is not stored in discrete locations, as is the case in conventional computers, but instead is stored as weighted connections between large numbers of processing elements. Machines of this type are often trained to recognize and classify particular patterns.

We can imagine a neural net where the connections between nodes are represented as electrical currents that flow through wires. Our particular machine has been in storage for a long time. When it was being placed into storage some of the wires came loose from their connections. We may repair the machine by reconnecting the wires to their proper connections (assuming we can tell where the loose wires belong). After completing these repairs we should have a fully functioning machine. Of course, we have no idea what patterns it has been trained to memorize. It would, in fact, be very difficult to try to determine what the machine knows without turning it on, since its memories exist only as connections between nodes.

The parallels with repair of a human brain after cryonic suspension are clear. Just because we can fix a brain does not mean we will understand the person contained in that brain. The point of all of this is that it is unreasonable to expect that during repair memory traces from a damaged brain will be automatically detected and enhanced. Instead, the availability of the original body may prove invaluable in helping the person to reconstruct their life, by providing a familiar physical environment to ease the transition into the second life cycle and by providing physical reminders of memories which may have been partially lost.


I have presented two arguments for preferring whole body suspensions to neurosuspensions. The first described a theory that information contained in the brain and DNA is necessarily incomplete and that the information loss incurred from disposal of the majority of the body may be critical. The second argument postulated that in cases of memory loss, the existence of the body might act as a crude type of memory backup and trigger recall of partial memories that might otherwise be lost.

How strongly do I feel about these issues? Strong enough to write this article and select the whole body route for myself. Strong enough to be concerned by the relatively small number of people selecting the whole body option. It seems to me that a conservative stance on this matter is prudent and that the whole body option is the conservative stance. The more information we preserve about ourselves the more likely our chance of rescue. Whole body-suspensions maximize the amount of information retained.

Of course, whole body suspensions are much more expensive than neurosuspensions. Full body patients are also more costly to maintain and less mobile. Currently the need for mobility is high. Had Dora Kent not elected neurosuspension, she would surely be dead now [5]. But, if cryonics gains even a limited acceptance, these advantages of neurosuspension will likely diminish. As our technology improves the advantages of the whole body approach will become more apparent.

In the final analysis each of us must weigh the costs and benefits of both approaches. For me, the potential benefits of a whole body suspension far outweigh the additional costs.


The above article was written to present some technical reasons for preferring whole body suspensions over neurosuspensions. I purposely omitted social and political reasons for selecting this option, because I feel a good case can be made solely on the technical merits of the two options. Since I drafted this article, however, the Thomas Donaldson case has become public, so I feel a few words concerning the social and political impact of neurosuspensions are now in order.

I saw the initial coverage of the Donaldson story on CNN. Their treatment was somewhat typical. While the taped report seemed balanced and fair, the introduction given to the piece concentrated on the "bizarre" aspects of the situation, emphasizing that Dr. Donaldson chose to have only his head preserved. The intention seemed to be to cast doubt on Dr. Donaldson's mental condition.

Cryonics is a radical concept. I think that we, as a group, would do well to consider the fact that no man, or organization, can survive in isolation. We need the cooperation of others -- doctors, lawyers, pharmaceutical companies, liquid nitrogen suppliers . . . the list is almost endless. Without these people, we are already dead.

The concept of neurosuspension is even more radical than the idea of whole body suspensions. Decapitation has historically been associated with death, not life, and thus can elicit a very strong emotional reaction. This seems to characterize my own family's view of cryonics. Most of my family does not object to the idea of my being frozen at death. In fact, my sister has agreed to be the executor of my estate. Their biggest concern was that I choose the whole body option. They, like most other "reasonable" people, believe that it will never be possible to restore a person from a "frozen head," and find the notion extremely repulsive.

Note that I used the word "believe" in the previous sentence. I have discussed, at length, the scenario envisioned for the restoration of neuropatients, and I have explained to them the necessity of nanotechnology to restore both whole body and neuropatients. They seem to intellectually understand, but they still don't truly "believe" it will ever be possible to revive a patient from neurosuspension.

I think that Dr. Donaldson's case would be taken much more seriously by the media and the public if he were signed up for a full body suspension. It is clear that a legislative test case should be selected with extreme care and all factors should be carefully weighed. When you consider the potential impact of this case on the future of the cryonics movement, and the obvious resistance caused by the neuro option, it would not have been unreasonable for Alcor to encourage Dr. Donaldson to sign up for a full body suspension, perhaps by arranging to absorb the additional cost.

After all, why should we throw another psychological roadblock in front of our path? The issue of paramount concern is the establishment of the right to premortem cryonic suspension, not the right to premortem neurosuspensions. Once the public and the law acknowledge our right to suspension, then recognition of neurosuspensions as a valid option will be much easier.

My personal belief is that Alcor, and the entire cryonics movement, would be better served if future members were strongly encouraged to consider the advantages of full body suspensions. Neurosuspensions could be presented as an intelligent fallback position, to be used under circumstances that preclude whole body suspensions, rather than as a primary option.


[1] "The Alcor Survey 1988-9 (Part I)" by Max O'Connor and Mike Perry, in Cryonics, Vol 10(9), September 1989, page 42.

[2] "Neuropreservation: Advantages and Disadvantages," Alcor publication NEUROPRE 9-88.

[3] "The Neuropreservation Controversy" by Paul Segall, in The American Cryonics Society Journal Vol 5(2), March 1988, pages 4-5.

[4] "But What Will the Neighbors Think?!: A Discourse on the History and Rationale of Neurosuspension" by Mike Darwin, in Cryonics, Vol 9(10), October 1988, pages 40-55.

[5] "A Timeline on the Events Surrounding the Cryonic Suspension of Dora Kent" in Cryonics, 9(1), January 1988, pages 1-7.